Golf club head having a textured striking face and method for manufacturing the same

Abstract

This specification comprehensively describes embodiments of a golf club head having a textured striking face, and a method for forming the club head through laser impact processing. [Solution] The golf club head may comprise a body and a striking face. The striking face has a textured front surface having an array of depressions. Each depression is 0.01 μm 2 (1×10 -8 mm 2 ) to 250,000 μm 2 (0.25mm 2 ) may have an occupied area between them. The textured front surface can influence the spin imparted to the golf ball upon impact. Other embodiments are described and may be claimed.

Description

[Technical Field]

[0001] (cross reference) This application claims priority to U.S. Provisional Patent Application No. 62 / 948,083 filed on 13 December 2019, U.S. Provisional Patent Application No. 62 / 976,987 filed on 14 February 2020, and U.S. Provisional Patent Application No. 63 / 198,112 filed on 29 September 2020, the contents of all of these are incorporated herein by reference.

[0002] This disclosure relates, in general, to golf equipment, and more particularly to golf club heads having a textured striking face. The surface texture or coefficient of friction of the striking face can affect the characteristic time of the golf club head and the spin imparted to the golf ball at impact. Furthermore, certain surface textures can also increase the fatigue resistance and wear resistance of the golf club head. [Background technology]

[0003] Laser shock peening (LSP) is a process that creates an array of laser shock impact zones. In the golf industry, this technique has been used solely to treat the face of a golf club to increase its hardness. By applying laser shock peening to the face of a golf club, a forged indentation (or depression) is created on the front surface of the face. During the laser shock treatment, the laser is shown to enter an absorption layer above the face being treated, passing through a confinement layer. The energy from the laser beam is absorbed by the absorption layer, which rapidly transforms this layer into plasma. The rapid generation of plasma creates a hammer-like shock wave that deforms the front surface of the face of the golf club, creating an indentation on the surface. The amount of laser light affects the amount of plasma generated. The amount of plasma, in turn, affects the intensity of the shock wave, which corresponds to the depth of the indentation (or depression).

[0004] Laser impact peening (LSP) has been used to introduce residual compressive stress into a specific portion of the striking face, creating a stress gradient between the treated and untreated areas of the striking face. Each laser pulse corresponds to the size of the laser beam, 4 mm 2 It processes areas larger than 4mm. 2 This only achieves processing of the impact face area of ​​the above size, and does not sufficiently change the coefficient of friction between the impact face and the golf ball. This technology presents a coefficient of friction with a fine texture (4mm) that produces the desired launch and spin characteristics when impacting the golf ball. 2 There is a need for a striking face having smaller depressions (or depressions) than the specified size. Furthermore, this technology also presents a need for a striking face with improved durability, fatigue resistance, and crack propagation. [Brief explanation of the drawing]

[0005] [Figure 1] The diagram shows a wedge-type golf club head having a textured striking face according to one embodiment, perpendicular to the face, and includes a close-up example of the textured area between the grooves.

[0006] [Figure 2] A diagram perpendicular to the face of a wedge-type golf club head having a fully textured striking face front surface according to one embodiment is shown.

[0007] [Figure 3] The image shows a wedge-type golf club head perpendicular to the face, having a striking face with a textured area on the front surface of the striking face, according to one embodiment.

[0008] [Figure 4] A perspective view of an array of square depressions according to one embodiment is shown.

[0009] [Figure 5] A perspective view of an array of hexagonal depressions according to one embodiment is shown.

[0010] [Figure 6] Figure 3 shows a view perpendicular to the surface of the array of square depressions.

[0011] [Figure 7] Figure 4 shows a view perpendicular to the surface of the hexagonal recess array.

[0012] [Figure 8A] Figure 6 shows a cross-sectional view of the array of square depressions in Figure 3, taken along line VI-VI in Figure 6, according to the first embodiment.

[0013] [Figure 8B] Figure 8A shows a cross-sectional view of the array of square depressions in Figure 3, taken along line VI-VI in Figure 6, according to a second embodiment having deeper depressions than the first embodiment in Figure 8A.

[0014] [Figure 9] Depth graphs of surface profiles (a), (b), (c), and (d) formed by shock waves from different laser light intensities in four embodiments are shown.

[0015] [Figure 10] This demonstrates how to process the face of a wedge using the Laser Impact Surface Patterning (LSSP) process.

[0016] [Figure 11] A top view of a production apparatus equipped with a base plate and frame according to one embodiment is shown.

[0017] [Figure 12] Figure 10 shows a top view of the production apparatus without the frame.

[0018] [Figure 13]The graphs show the launch angles for a control standard club head and an example club head, as tested under wet and dry conditions.

[0019] [Figure 14] The graphs show the spin rates for a control standard clubhead and an example clubhead, according to tests conducted under both wet and dry conditions.

[0020] [Figure 15] The graphs show ball speeds for a control standard clubhead and an example clubhead, according to tests conducted under both wet and dry conditions.

[0021] [Figure 16] The graph shows the statistical area for the control standard club head and the example club head, according to tests conducted under both wet and dry conditions. [Modes for carrying out the invention]

[0022] All print publications cited herein are incorporated herein by reference in their entirety, except where any definition, subject matter is denied or waived, or where incorporated material is inconsistent with the express disclosure herein. In such cases of inconsistency, the language of this disclosure shall prevail.

[0023] The invention described herein is a golf club head having a textured surface with a plurality of indentations. The textured surface can be a body surface such as a front surface of the striking face, a rear surface of the striking face, or a sole surface. In some embodiments, a plurality of surfaces are textured. The front surface of the striking face, the rear surface of the striking face, and / or the sole surface can be textured through a laser shock surface patterning (LSSP) process or a texturing process that is similar to but clearly different from the laser shock peening (LSP) process. The LSSP process is different from the existing LSP process because the LSSP process results in a higher coefficient of friction between the treated surface and the golf ball. The laser shock surface patterning process creates forging indentations (i.e., having an occupied area of 0.01 μm 2 (1×10 2 mm -8 ) to 250,000 μm 2 (0.25 mm 2 ) that are significantly smaller than prior art indentations (i.e., having an occupied area of 4,000,000 μm2 (4 mm 2 ) or more) created using the previous LSP process. Also, the laser shock surface patterning (LSSP) process described herein creates a clearly defined boundary for the forging indentation (or depression). The textured surface described herein can have a higher coefficient of friction than a surface lacking the LSSP texture. For embodiments having a textured front surface of the striking face, the plurality of indentations can improve shot performance, particularly under wet conditions. In particular, by applying texturing to the striking face using the LSSP process, it is possible to lower the launch angle, increase ball spin, and maintain ball speed.

[0024] The depressions created using LSSP have clearly defined boundaries that control the resulting coefficient of friction between the clubface and the golf ball. For low-loft clubheads, the increased coefficient of friction can improve the ball's flight path, including spin rate and launch angle, especially in wet conditions. By treating at least one surface of the clubface using LSSP, a finer grain structure can be created and compressive residual stress can be introduced, improving fatigue resistance, durability, and energy storage mechanics. The LSSP process described herein can also be used to relieve stress in weld zones, creating a more aerodynamic surface. definition

[0025] The golf club heads described herein may have a loft angle, which is measured as the angle between the contact surface and the surface tangent to the center point of the striking face. Generally, driver-type club heads have a lower loft angle than iron-type or wedge-type club heads.

[0026] As used herein, “low loft” may refer to a golf club head with a loft angle of less than 18 degrees. As used herein, “high loft” may refer to a golf club head with a loft angle of 18 degrees or more. However, the 18-degree cutoff value can be shifted by up to plus or minus 4 degrees for some designs, based on the desired performance target of a particular golf club head.

[0027] As used herein, “laser impact peening,” abbreviated as “LSP,” is a surface treatment process that treats a surface by forging a depression equal to the spot size of the laser beam used in the process. The laser beam spot size (and the resulting depression size) is 4 mm 2 or more or 5mm 2That concludes the explanation. The LSP process may include placing an absorption layer on top of the surface being processed, placing a confinement layer on top of the absorption layer, and irradiating the absorption layer with a laser through the confinement layer to convert it into a plasma. The creation of the plasma generates a shock wave that deforms or forges the surface beneath the absorption layer, creating a depression that matches the spot size of the laser beam.

[0028] "Laser impact surface patterning," abbreviated as "LSSP," as used herein, is a method of giving texture to a surface using a 0.01 μm pattern. 2 (1×10 -8 mm 2 ) to 250,000 μm 2 (0.25mm 2 LSSP is a process of treating a surface by forging at least one or more depressions (multiple depressions) each having an occupied area between them. In other words, each depression has an occupied area significantly smaller than the spot size of the laser beam used during the LSSP process. The LSSP process uses a mask layer (also called a mesh) to prevent the laser beam from affecting a particular area of ​​the surface being treated. In this way, the mask layer allows many micro-depressions to be created using each single laser shock. The LSSP process may include placing a mask layer (mesh) on the surface being treated, placing an absorption layer on top of the mask layer, placing a confinement layer on top of the absorption layer, and irradiating the absorption layer with a laser through the confinement layer to convert it into a plasma. Plasma creation is achieved by causing a shock wave moving through the aperture of the mask layer to deform or forge the surface below the aperture, creating depressions that match the aperture size of the mask layer. The portion of the surface covered by the mask (mesh) material is protected from the shock wave and is therefore left unforged.

[0029] As used herein, "golf ball" refers to a urethane-coated golf ball. The coefficients of friction described below were measured between a metal striking face and a urethane-coated golf ball.

[0030] As used herein, "treated surface" can be understood to include the treated surface layer and any adjacent material layers affected during the surface treatment. In other words, "treated surface" can refer to any material that exhibits an altered grain structure after the LSSP process. When used in the context of discussing the coefficient of friction, "treated surface" can refer only to the exposed surface layer. In these cases, the "treated surface" may have a measurable coefficient of friction relative to an external object, such as a golf ball.

[0031] As used herein, "launch angle" refers to the angle between the ground surface and the average trajectory of the golf ball at the time of impact between the golf ball and the golf club head, or immediately after impact.

[0032] As used herein, “dry conditions” may refer to a state in which the striking face has no visible moisture on its front surface. “Dry conditions” may also refer to weather conditions in which there is no rain, dew, condensation, or other form of moisture that could interfere with the contact between the golf ball and the striking face of the golf club head.

[0033] As used herein, “wet conditions” may refer to a state in which the striking face has visible moisture on its foreground surface. “Wet conditions” as used herein may also refer to weather conditions including rain, dew, condensation, or other forms of moisture that interfere with the contact between the golf ball and the striking face of the golf club head. Hitting a shot from tall grass is also considered a wet condition.

[0034] As used herein, a “flat” or “flat” surface may refer to a surface with an Ra value of about 1 μm (1000 nm) or less. In some embodiments, a “flat” or “flat” surface may have an Ra value of less than 0.02 μm (20 nm).

[0035] The textured striking face surface and / or textured body surface described herein comprises an array of forged depressions. Each forged depression (or recess) has a surface-occupied area and a maximum depth. The occupied area of ​​each depression is 0.01 μm. 2 From 250,000 μm 2 The depth of each forged recess ranges from 0.1 μm to 15 μm. The laser impact surface patterning (LSSP) process compresses the material grain structure of the treated surface in addition to altering the surface texture. Recessed texturing controls the coefficient of friction of the treated surface relative to the surface of a golf ball. When the striking face is a treated surface, the coefficient of friction increases, which can improve shot performance by lowering the launch angle, increasing ball spin, and maintaining ball speed. Recessed texturing can also control the residual stress (related to the compression / forging structure of the material) and aerodynamic properties of the treated surface. Additional benefits of recessed texturing may include, but are not limited to, slowing crack propagation, reducing material fatigue, and / or increasing energy storage during impact.

[0036] The golf club head 10 described herein may comprise a body 24 and a striking face 12. The body 24 defines a front portion, a rear portion opposite the front portion, a top rail 30, a sole 36 opposite the top rail 30, a sole leading edge 40 at the junction of the striking face 12 and the sole 36, a toe end 42, a heel end 44 opposite the toe end 42, and a hosel 46 connected to the heel end 44. When the golf club is in the address position, the top rail 30 forms the upper part of the club head 10, and the sole 36 forms the bottom part of the club head 10. The striking face 12 has a geometric center 14. The striking face 12 forms the striking surface for impacting the golf ball. In some embodiments, the striking face 12 is formed by a face plate, which is fitted into a recess in the front portion of the body 24.

[0037] The striking face 12 may have a front surface 16 and a rear surface (not illustrated) opposite to the front surface 16. The sole 36 may have a sole surface. At least a portion of the sole surface may be configured to engage with a turf or the ground when a golfer uses the golf club. The top rail 30 may have a top rail surface. The golf club head may be a driver type, fairway wood type, hybrid type, or iron type golf club head. Driver type, fairway wood type, and hybrid type club heads may have a crown rather than a top rail.

[0038] The golf club head 10 can be textured using one or more recess arrays 50 that extend across one or more of the entire front surface 16 of the striking face, the rear surface of the striking face, and / or the sole surface. Any of the recess arrays 50 may also be called a plurality of recesses, a textured array, a surface texture, and / or a geometric friction shape. The texture on the front surface 16 of the striking face, the rear surface of the striking face, and / or the sole surface can be formed using a laser impact surface patterning (LSSP) process. The rear surface of the striking face and / or the sole surface can be textured in the same way as the front surface 16 of the striking face, as described below. In some embodiments, only the front surface 16 of the striking face is textured using the recess array 50. In some embodiments, only the rear surface of the striking face is textured using the recess array 50. In some embodiments, only the sole surface is textured using the recess array 50.

[0039] In other embodiments, the front surface 16 of the striking face may have one or more depressions 50. For example, the front surface 16 of the striking face may be textured using a first set of depressions 50 (first array), and the rear surface of the striking face may be textured using a second set of depressions (second array). In yet another embodiment, the front surface 16 of the striking face may be textured using a first set of depressions 50 (first array), and the sole surface may be textured using a second set of depressions (second array). Alternatively, the front surface 16 of the striking face may be textured using a first set of depressions 50 (first array), the rear surface of the striking face may be textured using a second set of depressions (second array), and the sole surface may be textured using a third set of depressions (third array). In some embodiments, a single, textured surface may comprise a plurality of recess arrays 50.

[0040] This golf club head can be formed from a metallic material. In some embodiments, the striking face 12 can be formed from a different metal than the rest of the club head 10. Examples of metals may include, but are not limited to, steel, alloy steel, stainless steel, stainless alloy steel, C300, C350, Ni (nickel)-Co (cobalt)-Cr (chromium)-alloy steel, 8620 alloy steel, S25C steel, 303SS, 17-4SS, carbon steel, maraging steel, 565 steel, AISI type 304 or AISI type 630 stainless steel, titanium alloy, Ti-6-4, Ti-3-8-6-4-4, Ti-10-2-3, Ti15-3-3-3, Ti15-5-3, Ti185, Ti6-6-2, Ti-7s, Ti-9s, Ti-92, or Ti-8-1-1 titanium alloy, amorphous alloy, or other similar metals. The material of the golf club head can affect the amount of laser light required to achieve certain indentation parameters, such as the maximum indentation depth described below. Textured surface on the front of the striking face

[0041] Referring to Figures 2 to 5, the striking face front surface 16 has a texturing area 48. The texturing area 48 may have a different surface roughness than the rest of the striking face front surface 16. The different surface roughness of the texturing area 48 can be achieved by applying a laser impact surface patterning (LSSP) process to the texturing area 48 to create a number of depressions 50. The texturing area 48 can cover between 20% and 100% of the striking face front surface 16. In the embodiment of Figure 2, the texturing area 48 covers the entire front surface 16 (about 100% of the front surface 16). In some embodiments, the texturing region 48 can cover 20% to 30%, 30% to 40%, 40% to 50%, 50% to 60%, 60% to 70%, 70% to 80%, 80% to 90%, or 90% to 100% of the front surface 16. In some embodiments, the texturing region 48 covers 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the front surface 16.

[0042] In some embodiments, such as the embodiment in Figure 3, the texturing area 48 may be located only in a portion of the striking face 12 that also has conventional grooves 130. In other embodiments, the majority of the texturing area 48 may be located within the low area 20 of the striking face 12. The low area 20 may be any portion of the striking face 12 below the horizontal reference axis 72 extending through the geometric center 14 of the striking face. In other embodiments, the majority of the texturing area 48 may be located within the high area 22 of the striking face 12. The high area 22 may be any portion of the striking face 12 above the horizontal reference axis 72. In some embodiments, the texturing area 48 may have a height 58 that is greater than 0.2 inches, greater than 0.4 inches, greater than 0.6 inches, greater than 0.8 inches, greater than 1.0 inch, greater than 1.2 inches, greater than 1.4 inches, greater than 1.6 inches, greater than 1.8 inches, or greater than 2 inches, measured from the sole 36 to the top rail 30. By primarily positioning the texturing area 48 within the low area 20 or high area 22 of the striking face 12, the spin imparted to the golf ball during low or high hits can be altered, respectively. In some embodiments, the front surface 16 of the striking face can be selectively texturized within a specific area to create a striking face 12 that responds with substantially the same spin regardless of where the golf ball impacts the striking face 12. Furthermore, by selectively texturizing one or more portions of the front surface 16 of the striking face, the residual (internal) stress of the striking face can be altered, changing the durability, deformation characteristics, and energy storage mechanics of the striking face.

[0043] As illustrated in the close-up perspective views of Figures 4 and 5, the texturing region 48 comprises a plurality of recesses 50 that give texture to the front surface 16. The plurality of recesses 50 may also be called a recess array. The plurality of recesses 50 can be positioned in a pattern across the entire area of ​​the texturing region 48 and across at least a portion of the entire front surface 16 of the striking face. The plurality of recesses 50 can cover between 20% and 100% of the front surface 16 of the striking face, as well as the coverage of the texturing region 50. In some embodiments, the plurality of recesses 50 can cover 20% to 30%, 30% to 40%, 40% to 50%, 50% to 60%, 60% to 70%, 70% to 80%, 80% to 90%, or 90% to 100% of the front surface 16. In some embodiments, the multiple depressions 50 can cover 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the front surface.

[0044] Referring to Figures 2, 4, and 5, a plurality of depressions 50 (depression array) may comprise a plurality of individual depressions 100 (also called “recesses”). The plurality of depressions 50 can be arranged in any pattern and oriented in any direction throughout the club head. The layout of the plurality of depressions 50 may differ between embodiments. In some embodiments, the plurality of depressions 50 can be arranged in a row pattern. The plurality of depressions 50 can further be arranged in columns. The rows of depressions can be oriented linearly. The depression array orientation can be defined as a direction parallel to the linear orientation of the rows. The depression array orientation can be represented by an array axis 70. In some embodiments, the plurality of depressions 50 (depression array) can be oriented horizontally. Referring to Figure 2, it is shown that the horizontal reference axis 72 extends from the heel end 44 to the toe end 42 of the club head 10, via the geometric center 14 of the striking face 12. The array axis 70 (expressing recessed array orientation) can be offset from the horizontal reference axis 72 by an angle of ±0 to 90 degrees. In some embodiments, the array axis 70 is offset from the horizontal reference axis 72 by + / -10 degrees, + / -20 degrees, + / -30 degrees, + / -40 degrees, + / -45 degrees, + / -50 degrees, + / -60 degrees, + / -70 degrees, + / -80 degrees, or + / -90 degrees.

[0045] In some embodiments, the rows of depressions can be arched or curved. The rows of depressions can be concave with respect to the sole 36 of the club head, concave with respect to the top rail 30, concave with respect to the heel end 44, concave with respect to the toe end 42, concave with respect to the upper toe end, concave with respect to the upper heel end, concave with respect to the lower toe end, or concave with respect to the lower heel end. In some embodiments, the multiple depressions can extend radially from the geometric center 14 of the striking face 12. The multiple depressions can form a circular row having a diameter that increases with respect to the geometric center 14 of the striking face. Alternatively, the multiple depressions can form an oval, elliptical, rectangular / oval, square, rectangular, triangular, or any other suitably shaped row with respect to the geometric center 14 of the striking face 12. In some embodiments, the centers of the multiple depressions are defined with respect to a point offset from the geometric center 14 of the striking face 12.

[0046] Multiple depressions 50 are 1 cm 2 The number of depressions per unit area ranges from approximately 3,040 to 75,950, indicating a depression density (1 in 2 It may have approximately 19,600 to 490,000 depressions per unit area. In some embodiments, the depression density is 1 cm 2 There may be approximately 3,000 to 5,000, 5,000 to 10,000, 10,000 to 30,000, 30,000 to 60,000, or 45,000 to 75,950 depressions per unit area.

[0047] Referring to Figure 3, in some embodiments, the texturing area 48 may comprise a plurality of pocket areas 62 (also called laser spot areas / areas or laser cover areas / areas). Each pocket area 62 may correspond to the spot size of the laser beam used during the LSSP process. However, the LSSP process uses a mask layer (mesh) to protect multiple portions of the surface during processing. Therefore, each pocket area 62 has a portion that is a masked (protected) surface area and a portion that is an exposed (unprotected) surface area. The exposed surface area becomes a plurality of depressions 50. The reason for the creation of the plurality of depressions 50 is that a portion of the pocket area 62 is exposed to the plasma shock wave through the aperture of the mask layer during LSSP. Due to the mask layer (mesh), each pocket area 62 may comprise a plurality of depressions 50. The pocket areas 62 may be circular, square, hexagonal, triangular, or any other suitable shape. The pocket areas 62 may be arranged in a pattern or array across the entire area of ​​the texturing area 48. The pocket regions 62 can be located right next to each other to form rows. By positioning the rows of pocket regions 62 between the grooves 130, the area of ​​the front surface 16 between the grooves 130 can be textured.

[0048] In some embodiments, the pocket regions 62 correspond to the spot size of the laser beam used during the LSSP process. In circular pocket regions, each pocket region 62 may have a spot size (diameter) of 1 mm to 5 mm. In some embodiments, the spot sizes may be 1 mm to 3 mm, 1.5 mm to 3.5 mm, 2 mm to 4 mm, 2.5 mm to 4.5 mm, or 3 mm to 5 mm. For example, the spot sizes may be 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm. In some embodiments, pocket regions 62 may be separated from other pocket regions 62 by less than about 0.1 mm (100 μm).

[0049] Each pocket region 62 can have 10 to 15,500 depressions. In some embodiments, each pocket region 62 can have depressions ranging from 10 to 100, 100 to 500, 500 to 1000, 1000 to 5000, 5000 to 10,000, 10,000 to 15,500, or any intermediate range of depressions. For example, in a circular pocket region 62 with a diameter of 1 mm, each pocket region 62 can have approximately 10 to 610 depressions. For example, in a circular pocket region 62 with a diameter of 5 mm, each pocket region 62 can have approximately 500 to 15,500 depressions. The multiple depressions 50 within the pocket region 62 provide roughness to the texturing region 48 and change the coefficient of friction between the texturing region 48 and the golf ball.

[0050] Referring to Figures 4 to 6, each recess 100 of the plurality of recesses 50 has a certain occupancy shape, as can be seen when viewed perpendicularly from the front surface 16 of the striking face. The occupancy shape may be a parallelogram, rectangle, square, diamond (or rhombus), circle, triangle, pentagon, hexagon, or any other suitable shape. In some embodiments, the occupancy shape may have one continuous side, two arched sides, three sides, four sides, five sides, six sides, seven sides, eight sides, nine sides, or ten sides. Each recess 100 is provided with side walls 106, which extend into the front surface 16 to form the recess 100. The recess side walls 106 correspond to the sides of the occupancy shape in a plane coinciding with the front surface 16. In some embodiments, the plurality of recesses 50 may include recesses having different occupancy shapes on the same striking face. In some embodiments, a section of the striking face 12 may have a first array of recessed shapes, and another section of the striking face 12 may have a second array of recessed shapes. For example, the first recessed shape may be a hexagon, and the second recessed shape may be a square. In some embodiments, a single array of recesses may have any combination of multiple occupied shapes. For example, a single array may have hexagons and triangles. As a further example, a single array may have hexagons, squares, and triangles. As a further example, a single array may have circles and squares. As a further example, a single array may have rectangles and squares.

[0051] Referring to Figures 6 and 8, the occupied shape can be enclosed by a surface occupied area 102. In other words, the occupied area 102 is the area enclosed by the recessed side wall 106 in a plane that coincides with the front surface 16. The occupied area 102 of each recess is 0.01 μm. 2 From 250,000 μm 2 This is possible. In some embodiments, the occupied area 102 of each depression is 0.01 μm 2 From 0.10 μm 2 , 0.10 μm 2 From 0.20 μm 2 , 0.20 μm 2 From 0.30 μm2 , 0.30 μm 2 From 0.40 μm 2 , 0.40 μm 2 From 0.50 μm 2 , 0.50 μm 2 From 1.0 μm 2 , 1.0 μm 2 From 10 μm 2 , 10 μm 2 From 50 μm 2 , 50 μm 2 From 100 μm 2 , 100 μm 2 From 200 μm 2 , 200 μm 2 From 300 μm 2 , 300 μm 2 From 400 μm 2 , 400 μm 2 From 500 μm 2 , 500μm 2 From 600 μm 2 , 600 μm 2 From 700 μm 2 , 700 μm 2 From 800 μm 2 , 800 μm 2 From 900 μm 2 , 900 μm 2 From 1000 μm 2 , 1000μm 2 From 3000 μm 2 , 3000μm 2 From 6000 μm 2 , 6000μm 2 From 9000 μm 2 , 9000μm 2 From 12,000 μm 2 , 12,000 μm 2 From 15,000 μm 2 , 15,000 μm 2 From 30,000 μm 2 30,000 μm 2 From 60,000 μm 2 , 60,000 μm 2 From 100,000 μm 2 , 100,000 μm 2 From 150,000 μm 2, 150,000 μm 2 From 200,000 μm 2 , or 200,000 μm 2 From 250,000 μm 2 This is possible. The small surface-occupying area 102 also allows a portion of the striking face 12 to be selectively processed without affecting the rest of the striking face 12.

[0052] Referring to Figures 4 to 8, each of the recesses 100 of the multiple recesses 50 on the front surface 16 of the striking face may have a bottom surface 126 and a side wall 106 (also called a side or edge). Some recesses 100 may have a first side wall 108, a second side wall 110 opposite the first side wall 108, an upper side wall 112, and a lower side wall 114. The side walls 106 may have a sharper and sharper geometric shape compared to side walls formed by a conventional LSP process. Referring to Figures 8A and 8B, the side walls 106 connect to the front surface 16 of the striking face almost perpendicularly. The corner-like intersection between the side wall 106 and the front surface 16 of the striking face may be slightly rounded.

[0053] The amount of curvature at the intersection between the side wall 106 and the front surface 16 can be characterized by the radius of curvature 116 of a reference circle along the cross-sectional outline of the intersection. The radius of curvature of the intersection can also be called the exit radius. The radius of curvature 116 of the reference circle can be between one-tenth and one-hundredth of the radius of curvature of the intersection of the depression formed by the LSP process. In some embodiments, the radius of curvature 116 can be one-tenth, one-twentieth, one-thirtieth, one-fortieth, one-fiftieth, one-sixtieth, one-seventieth, one-eighth, one-ninetieth, or one-hundredth of the radius of curvature of the depression intersection (geometric exit shape) formed by the LSP. During the LSP process, each laser beam impact forms a single depression without masking to block any portion of the laser beam. The edge of the laser beam imparts a gentle forging effect across the entire surface area that becomes the intersection or geometric exit shape of the depression. In other words, the LSP process creates depressions with a sloped geometric exit shape rather than a sharp geometric exit shape. Using the same laser light intensity, the LSP process creates large, rounded depressions, while the LSSP process creates small, sharp depressions.

[0054] In the golf industry, media blasting is also used to texturize surfaces. Media blasting modifies the morphology of a workpiece surface by relying on high-speed solid matter impacting. Each particle of the solid matter can travel at an unknown speed and in an unknown direction, creating overlapping treatments that flatten the surface. Both peaks (any feature higher than the initial elevation of the surface) and valleys (any feature lower than the initial elevation of the surface) can grow, resulting in an uneven surface with sharp peaks. However, repeated impacting of the same surface area with solid matter, and the size of the particles themselves, result in shallow valleys. Therefore, media blasting cannot produce both sharp edges and deep depressions to obtain increased friction. In contrast, the LSSP process can produce deep and sharp depressions (small radius of curvature at intersections or exit edges).

[0055] Another form of surface texturing used in the golf industry is laser etching. Laser etching removes material from a surface by ablating it into vapor. The treated surface transitions from solid to liquid, gas, liquid, and back to solid. Metals harden as they re-solidify. The morphology of a laser-etched surface is characterized by shallow valleys and rounded peaks. The LSSP process can produce deep and sharp depressions by using a mask layer (mesh) to guide and control shock waves to create micro-features referred to herein as depressions 100. Neither the LSP process, media blasting, nor laser etching can independently control depression parameters such as position, spacing (separation distance), and edge sharpness (intersection radius of curvature).

[0056] The side walls 106 can be connected to the recessed bottom surface 126 almost perpendicularly, in the same manner that they are connected to the front surface 16 of the striking face. In other words, the side walls 106 can form a sharp radius of curvature with respect to the recessed bottom surface 126.

[0057] Referring to Figures 6-8, in some embodiments, each recess 100 includes a width 120 measured in a direction parallel to the array axis 70 of the recess array 50. In embodiments having a horizontal recess array, the width 120 is measured in the direction from the heel end 44 to the toe end 42 (heel-toe direction). In some embodiments, the width 120 can span from the first side wall 108 to the second side wall 110 of the recess 100. The width 120 is measured through the center point 104 of the recess. For example, the width of a circular recess is equal to the diameter of the circular recess. The width 120 of a recess ranges from 0.1 μm to 500 μm (approximately 3.9 × 10⁻¹⁶ μm). -6It can range from an inch to approximately 0.0197 inches. In some embodiments, the width 120 of the depression may be in the range of 0.1 μm to 0.5 μm, 0.5 μm to 1 μm, 1 μm to 5 μm, 5 μm to 10 μm, 10 μm to 20 μm, 20 μm to 30 μm, 30 μm to 40 μm, 40 μm to 50 μm, 50 μm to 60 μm, 60 μm to 70 μm, 70 μm to 80 μm, 80 μm to 90 μm, 90 μm to 100 μm, 100 μm to 150 μm, 150 μm to 200 μm, 200 μm to 250 μm, 250 μm to 300 μm, 300 μm to 350 μm, 350 μm to 400 μm, 400 μm to 450 μm, or 450 μm to 500 μm. In some embodiments, the width of the depression is 0.1 μm, 0.5 μm, 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm, The possible widths are 240 μm, 250 μm, 260 μm, 270 μm, 280 μm, 290 μm, 300 μm, 310 μm, 320 μm, 330 μm, 340 μm, 350 μm, 360 μm, 370 μm, 380 μm, 390 μm, 400 μm, 410 μm, 420 μm, 430 μm, 440 μm, 450 μm, 460 μm, 470 μm, 480 μm, 490 μm, and 500 μm. In some embodiments, such as the multiple hexagonal depressions shown in Figure 7, each depression 100 may include a side width 118 (also called sidewall length) smaller than the width 120 measured through the center 104 of the depression 100.

[0058] Referring to Figures 6 and 7, in some embodiments, each recess 100 has a height 122, measured in a direction perpendicular to the array axis 70 of the recess array 50. In some embodiments, the width 122 extends between the upper side wall 112 and the lower side wall 114. For a horizontally oriented recess array 50, the recess height 122 may be measured along the front surface 16 of the striking face in the direction from the sole leading edge 40 of the club head toward the top rail 30. For some recesses 100, the recess height 122 may be the same as the recess width 120.

[0059] The height of the depression is 122, ranging from 0.1 μm to 500 μm (approximately 3.9 × 10⁻¹⁰). -6 It can be approximately 0.0197 inches. In some embodiments, the height 122 of the depression may be in the range of 0.1 μm to 0.5 μm, 0.5 μm to 1 μm, 1 μm to 5 μm, 5 μm to 10 μm, 10 μm to 20 μm, 20 μm to 30 μm, 30 μm to 40 μm, 40 μm to 50 μm, 50 μm to 60 μm, 60 μm to 70 μm, 70 μm to 80 μm, 80 μm to 90 μm, 90 μm to 100 μm, 100 μm to 150 μm, 150 μm to 200 μm, 200 μm to 250 μm, 250 μm to 300 μm, 300 μm to 350 μm, 350 μm to 400 μm, 400 μm to 450 μm, or 450 μm to 500 μm. In some embodiments, the height of the depression is 0.1 μm, 0.5 μm, 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, 210 μm, 220 μm, 230 μm. The possible thicknesses are 240μm, 250μm, 260μm, 270μm, 280μm, 290μm, 300μm, 310μm, 320μm, 330μm, 340μm, 350μm, 360μm, 370μm, 380μm, 390μm, 400μm, 410μm, 420μm, 430μm, 440μm, 450μm, 460μm, 470μm, 480μm, 490μm, and 500μm.

[0060] Referring to FIGS. 8A and 8B, each recess 100 includes a maximum depth 124. The embodiment of FIG. 8B has a deeper recess than the embodiment of FIG. 8A, and the maximum depth 124 is larger. The maximum depth 124 of the recess can be measured perpendicular to the front surface 16 of the striking face. In other words, the maximum depth 124 of the recess can be measured from the plane coinciding with the front surface 16 of the striking face to the bottom surface 126 of the recess. The maximum depth 124 of each recess can range from 0.1 μm to 15 μm. In some embodiments, the maximum depth 124 of the recess can be in the range of 0.1 μm to 0.5 μm, 0.5 μm to 0.9 μm, 0.8 μm to 1.2 μm, 1.0 μm to 3.0 μm, 3.0 μm to 5.0 μm, 5.0 μm to 7.0 μm, 7.0 μm to 9.0 μm, 9.0 μm to 11 μm, 11 μm to 13 μm, 13 μm to 15 μm. In some embodiments, the maximum depth of the recess can be 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, or 15 μm. The depth 124 of each recess 100 affects the coefficient of friction of the front surface 16 of the striking face.

[0061] When the recesses 100 are formed by laser shock peening (LSSP), the depth 124 of each recess 100 correlates with the intensity of the laser beam. The maximum recess depth 124 can vary slightly for different striking face materials. In the case of polished carbon steel, the depth 124 of the recesses described above is up to 2000 GW / cm 2 , up to 1500 GW / cm 2 , up to 1000 GW / cm 2 , up to 500 GW / cm 2 , up to 250 GW / cm 2 , up to 100 GW / cm 2 , up to 50 GW / cm 2 , up to 25 GW / cm 2 , up to 10 GW / cm 2 , up to 5 GW / cm 2 , or up to 1 GW / cm 2This can be achieved by the laser brightness. In some LSSP processes, the maximum depression depth given a laser beam intensity can be approximated by the following equation: y = 0.0075x + 0.5949 Here, "x" is the intensity of the laser beam, and "y" is the approximate maximum depression depth of 124 resulting from the use of a given laser beam intensity in the LSSP process.

[0062] Each depression 100 has a bottom surface 126. In some embodiments, the depression bottom surface 126 may have a non-uniform profile with ridges, valleys, and other complex geometric shapes. In some embodiments, the depression bottom surface 126 may have a shock wave shape with a curved contour. The shock wave shape and / or non-uniform profile can be created through the laser shock surface patterning (LSSP) process described below. The contour of the bottom surface 126 may vary due to the grain structure in the depression before processing and / or due to the composition of the absorption layer used in the LSSP process. For example, if the absorption layer contains large particles, the shock wave power will be greater, which will affect the shaping of the depression bottom surface 126.

[0063] Figure 9 illustrates the results of an experiment documented in the publication Mao, Bo & Siddaiah, Arpith & Menezes, Pradeep & Liao, Yiliang. (2018). "Surface Texturing by indirect laser shock surface patterning for manipulated friction coefficient", Journal of Materials Processing Tech. vol. 257 (2018) pp. 227 - 233), which is hereby incorporated by reference in its entirety. Since these graphs have not been modified from their original source, the vertical axis of "Height (μm)" corresponds to the measured value of "recess depth" as defined in this specification. Figure 9 illustrates the surface profiles of four examples of surfaces each having a plurality of recesses. The surface profile (a) of the first example was created by subjecting a polished square carbon steel plate to laser shock surface patterning with a laser fluence of 0.484 GW / cm 2 The first surface profile (a) shows a pattern of recesses with a consistent depth (approximately 0.2 μm) and width. The bottom surface of each recess shows a slight protrusion at the center of each bottom surface. The surface profile (b) of the second example was created by subjecting a polished square carbon steel plate to laser shock surface treatment with a laser fluence of 0.554 GW / cm 2 The second surface profile (b) has recesses with a greater depth (approximately 0.5 μm). The bottom surface of each recess is slightly more irregular than in the first surface profile (a).

[0064] The surface profile (c) of the third example was created by subjecting a polished square carbon steel plate to laser shock surface treatment with a laser fluence of 0.778 GW / cm 2 The surface profile (d) of the fourth example was created by subjecting a polished square carbon steel plate to laser shock surface treatment with a laser fluence of 0.890 GW / cm 2The surfaces were created by laser impact surface patterning with a laser light intensity of [value]. Surface profiles (c) of the third embodiment and (d) of the fourth embodiment have progressively greater depths than profiles (a) and (b). The third profile (c) and the fourth profile (d) include peaks and irregular textures extending from the bottom surface. The effect of laser light intensity on the surface profiles is discussed further below.

[0065] Multiple depressions 50 in the processing area 40 can be characterized by the aspect ratio of the depression depth 124 to the depression width 120. The aspect ratio can range from 3 to 150. In some embodiments, the aspect ratio may be in the range of 3 to 5, 5 to 10, 10 to 20, 20 to 30, 30 to 40, 40 to 50, 50 to 60, 60 to 70, 70 to 80, 80 to 90, 90 to 100, 100 to 110, 110 to 120, 120 to 130, 130 to 140, 140 to 150, 3 to 25, 25 to 50, 50 to 75, 75 to 100, 100 to 125, 125 to 150, 3 to 50, 25 to 75, 50 to 100, 75 to 125, 100 to 150, 3 to 100, 25 to 125, or 50 to 150. Higher aspect ratios correlate with rougher surfaces and higher coefficients of friction. For aspect ratios greater than 6, "micro-effects" and "nano-effects" occur, resulting in better-than-expected performance of multiple depressions 50.

[0066] Referring again to Figure 2, multiple recesses 50 (recess arrays) can be arranged in a pattern across the front surface 16. Recess arrays 50 may include a length 78 measured in the heel-to-toe direction. In some embodiments, the array length 78 is limited by the size of the striking face 12. In some embodiments, such as Figure 3, the array length 78 may be equal to the length of one or more face grooves 130, as will be further described below. The array length 78 may be between 1.5 inches and 2.5 inches. In some embodiments, the array length 78 is 1.5 inches to 2.0 inches, 1.8 inches to 2.2 inches, or 2.0 inches to 2.5 inches. In some embodiments, the array length may be 1.5 inches, 1.6 inches, 1.7 inches, 1.8 inches, 1.9 inches, 2.0 inches, 2.1 inches, 2.2 inches, 2.3 inches, 2.4 inches, or 2.5 inches.

[0067] Referring to Figures 6-8, the depressions 100 may be spaced apart from each other by a separation distance 80 to create a depression array 50. The separation distance 80 can range from 1 μm to 250 μm (approximately 3.9 × 10⁻¹⁰). -5 The separation distance can be 1 inch to approximately 0.0098 inch. In some embodiments, the separation distance 80 may be 1 μm to 25 μm, 25 μm to 75 μm, 75 μm to 125 μm, 125 μm to 175 μm, 175 μm to 225 μm, or 225 μm to 250 μm. In some embodiments, the separation distance 80 may be 25 μm, 50 μm, 75 μm, 100 μm, 125 μm, 150 μm, 175 μm, 200 μm, 225 μm, or 250 μm. The separation distance 80 affects the density of depressions across the array 50, and as a result, the properties of the front surface 16, such as the coefficient of friction, change.

[0068] Multiple areas of the striking face 12 can be treated to have depressions 100 of different sizes and / or depths, thereby giving different coefficients of friction to multiple areas of the striking face. Furthermore, the multiple depressions 50 can be arranged or aligned in various patterns, including similar or different shapes, to alter the coefficient of friction, hardness, and / or aerodynamic properties of the surface. For example, in some embodiments, the depressions 100 can be aligned in a second pattern (second array) so as to be spaced further apart than in a first pattern (first array).

[0069] In addition to the recess array 50, the front surface 16 of the striking face may further comprise conventional grooves 130. The grooves 130 may extend generally horizontally from heel to toe when the club is in the address position. The grooves 130 may be spaced apart from each other in the direction from crown to sole (or from top rail to sole). The grooves 130 may be spaced apart by a groove pitch 132 (separation distance) between 2 millimeters (mm) and 3 mm (0.08 inches and 0.12 inches). In some embodiments, the groove pitch 132 is 2 mm to 2.2 mm, 2.2 mm to 2.4 mm, 2.4 mm to 2.6 mm, 2.6 mm to 2.8 mm, or 2.8 mm to 3.0 mm. In some embodiments, the groove pitch 132 may be 2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, or 3.0 mm. The recess array 50 can fill or partially fill the embedding area between the grooves 130. In some embodiments, the grooves 130 may have a constant width (width measured from the crown to the sole / width measured from the top rail to the sole) and a constant land area between the grooves 130. In other embodiments, the grooves 130 may have a width that varies between the grooves 130 and a land area that varies between the grooves 130. Textured surface on the back of the impact face

[0070] As described above, one or more of the front surface 16 of the striking face, the rear surface of the striking face, and the sole surface can be textured. The rear surface of the striking face may have at least one textured area, similar to the texturing area 48 described above. The texturing area may comprise a plurality of depressions that give texture to the rear surface (not illustrated). The plurality of depressions on the rear surface may be similar to the plurality of depressions 50 on the front surface 16. Similar to the texturized front surface, the texturing area on the rear surface may cover between 20% and 100% of the striking face. In some embodiments, the texturing area may cover 20% to 30%, 30% to 40%, 40% to 50%, 50% to 60%, 60% to 70%, 70% to 80%, 80% to 90%, or 90% to 100% of the rear surface. In some embodiments, the texturing area can cover 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the rear surface. By selectively texturing one or more portions of the rear surface, the residual stress on the rear surface can be altered, improving the durability, deformation characteristics, and energy storage mechanics of the striking face 16.

[0071] Multiple depressions on the rear surface of the striking face may have the same occupancy shape, occupancy area, depression width, depression height, and depression depth as those described above for each of the front surface depressions 100. In some embodiments, the rear surface of the striking face may have an array of first depression shapes, and another section of the rear surface may have an array of second depression shapes. In some embodiments having both a textured front and rear surface of the striking face, the depression shapes on the front surface may differ from those on the rear surface. In other embodiments having both a textured front and rear surface, the depression shapes on the front and rear surfaces may be identical. Multiple regions of the rear surface may be treated to give multiple regions of the rear surface different grain structures, residual stresses, and / or hardnesses by having depressions of different sizes and / or heights.

[0072] As described above, multiple depressions can be positioned in an array or pattern across the entire rear surface in a manner similar to the array 50 on the front surface 16. The array length and / or separation distance between depressions on the rear surface may be the same as those described above for the front surface 16 of the striking face. The separation distance affects the density of depressions across the entire array, consequently changing the properties of the rear surface, such as durability. Sole surface texture

[0073] In some embodiments, the sole surface has a plurality of depressions that give texture to the sole 36. The sole surface may have at least one texturing region, similar to the texturing region 48 described above. The texturing region may have a plurality of depressions that give texture to the sole surface. The plurality of depressions on the sole surface (not illustrated) may be similar to the plurality of depressions on the front surface and the rear surface. The texturing region on the sole surface may cover between 20% and 100% of the sole surface, similar to the texturized front surface and the texturized rear surface. In some embodiments, the texturing region on the sole may cover between 20% and 30%, 30% and 40%, 40% and 50%, 50% and 60%, 60% and 70%, 70% and 80%, 80% and 90%, or 90% and 100% of the sole surface. In some embodiments, the sole texture area can cover 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the sole surface. By selectively texturing one or more portions of the sole surface, the coefficient of friction, hardness, and / or aerodynamic properties of the sole surface can be altered. The altered coefficient of friction can improve turf interaction between the sole surface and the ground. The increased hardness of the sole surface can improve the durability of the sole. The altered aerodynamic properties can reduce drag and increase swing speed.

[0074] Multiple depressions on the sole surface may have the same occupancy shape, occupancy area, depression width, depression height, and depression depth as those of the depressions on the front and rear surfaces described above. In some embodiments, the sole surface may have an array of first depression shapes, and another section of the sole surface may have an array of second depression shapes. In embodiments having both a textured striking face and a textured sole, the depression shape of the striking face may be different from or identical to the depression occupancy shape of the sole. In some embodiments, multiple regions of the sole surface may be treated to have depressions of different sizes and / or depths, thereby giving multiple regions of the sole surface different grain structures and / or different residual stresses. Multiple treated regions of the sole surface may have different hardness values. The depression depth of the arrays on the sole surface may also affect the aerodynamic response and turf interaction of the sole surface.

[0075] As described above, multiple depressions can be positioned in an array or pattern across the entire sole 36. The array of depressions on the sole surface can cover a portion of the sole 36 or the entire sole 36. The array of depressions on the sole surface may have a length measured in the heel-toe direction. In some embodiments, the array length is limited by the size of the sole 36. In some embodiments, the array length of the sole may be longer than the array length of the front or rear surface of the striking face. The array length of the sole may be between 1.5 inches and 3.5 inches. In some embodiments, the array length is between 1.5 inches and 2.0 inches, between 1.8 inches and 2.2 inches, between 2.0 inches and 2.5 inches, between 2.5 inches and 3.0 inches, or between 3.0 inches and 3.5 inches. In some embodiments, the array length is 1.5 inches, 1.6 inches, 1.7 inches, 1.8 inches, 1.9 inches, 2.0 inches, 2.1 inches, 2.2 inches, 2.3 inches, 2.4 inches, 2.5 inches, 2.6 inches, 2.7 inches, 2.8 inches, 2.9 inches, 3.0 inches, 3.1 inches, 3.2 inches, 3.3 inches, 3.4 inches, or 3.5 inches.

[0076] Multiple depressions can be spaced apart by a certain separation distance to create a depression array on the sole surface. These depressions on the sole surface can be spaced apart by the same separation distance 80 described above for the depression array 50 on the surface in front of the striking face. The separation distance affects the density of depressions across the entire array, consequently altering properties of the sole surface such as durability, aerodynamic performance, and / or turf interaction. Alternative Embodiment with Crown Surface Texturing

[0077] In alternative embodiments (not shown), other body surfaces on the golf club head can be textured. For example, in wood-type golf club heads (driver, fairway, and hybrid), the crown surface of the club head may include at least one textured area having a plurality of depressions that give texture to the crown. In wood-type embodiments having a textured crown surface, the array width can be between 1.5 inches and 4.5 inches. In some embodiments, the array length is between 1.5 inches and 2.0 inches, 1.8 inches and 2.2 inches, 2.0 inches and 2.5 inches, 2.5 inches and 3.0 inches, 3.0 inches and 3.5 inches, 3.5 inches and 4.0 inches, or 4.0 inches and 4.5 inches. In some embodiments, the array width is 1.5 inches, 1.6 inches, 1.7 inches, 1.8 inches, 1.9 inches, 2.0 inches, 2.1 inches, 2.2 inches, 2.3 inches, 2.4 inches, 2.5 inches, 2.6 inches, 2.7 inches, 2.8 inches, 2.9 inches, 3.0 inches, 3.1 inches, 3.2 inches, 3.3 inches, 3.4 inches, 3.5 inches, 3.6 inches, 3.7 inches, 3.8 inches, 3.9 inches, 4.0 inches, 4.1 inches, 4.2 inches, 4.3 inches, 4.4 inches, or 4.5 inches. All other parameters of the crown recess array, such as recess width, recess height, recess depth, and separation distance, can be analogous to the respective parameters of the impact face front surface recess array 50. Properties / Characteristics / Performance

[0078] The textured or treated surface of a golf club head may exhibit different coefficients of friction, roughness, hardness, material grain structure, and / or residual stress compared to an untreated surface. One or more of these parameters can affect spin rate, launch angle, and / or ball speed. Further advantages may include efficient and rapid manufacturability, increased material fatigue resistance, and / or increased wear resistance.

[0079] The size and shape of the depressions on the front surface 16, the rear surface, and / or the sole surface can determine the coefficient of friction of each of these surfaces. The coefficient of friction between the urethane-coated golf ball and the textured front surface, the textured rear surface, and / or the textured sole surface may be in the range of 0.05 to 0.95. In some embodiments, the coefficient of friction of the textured surface between the urethane-coated golf ball and the textured surface may be in the range of 0.10 to 0.30, 0.40 to 0.95, 0.40 to 0.50, 0.50 to 0.60, 0.60 to 0.70, 0.70 to 0.80, 0.80 to 0.90, or 0.85 to 0.95. In some embodiments, the textured surface friction coefficient may be 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, 0.85, 0.90, or 0.95. In some embodiments, the textured surface friction coefficient may be less than 0.1, less than 0.2, less than 0.3, less than 0.4, less than 0.5, less than 0.6, less than 0.7, less than 0.8, less than 0.9, or less than 0.95.

[0080] In some embodiments, the treated front surface 16 of the striking face and / or the sole surface have a higher coefficient of friction than the untreated striking face and / or sole. In other embodiments, the treated front surface 16 of the striking face and / or the sole surface have a lower coefficient of friction than the untreated striking face and / or sole. In embodiments where the depressions are formed by laser impact surface treatment (LSSP), the coefficient of friction of the textured surface is determined by the amount of laser light used during manufacturing. The coefficient of friction of the striking face controls the spin imparted to the golf ball at impact. The coefficient of friction of the sole affects the turf interaction between the sole surface and the ground.

[0081] The coefficient of friction between the ball and the clubface 12 controls the amount of spin imparted to the golf ball at impact. The loft angle of the clubhead 10 can change the relationship between the coefficient of friction of the clubface and the amount of spin on the golf ball. With low-loft clubs, a higher coefficient of friction can result in less spin on the ball, while with high-loft clubs, a higher coefficient of friction can result in more spin. For most low-loft clubheads, lower spin is desirable because it allows for a longer carry distance. For example, with driver-type clubs, lower spin increases carry distance and allows the golf ball to roll forward after landing. However, with high-loft clubs, higher spin increases ball flight distance. Higher spin can also cause the ball to stop or roll slightly backward upon landing, thereby increasing shot accuracy.

[0082] In addition to the loft angle influencing the relationship between friction coefficient and spin rate, the conditions under which the shot is struck can also affect this relationship. In particular, for high-loft clubheads in dry conditions, the amount of ball spin imparted may not be affected by adding texture to the front surface of the striking face. However, in wet conditions, the amount of ball spin imparted can be increased by texturing the front surface of the striking face. The added texture can increase the spin rate by up to 2000 revolutions per minute (rpm). In some embodiments, the textures described herein can increase the spin rate under wet conditions by 500 rpm to 2000 rpm, 500 rpm to 700 rpm, 700 rpm to 900 rpm, 900 rpm to 1100 rpm, 1100 rpm to 1300 rpm, 1300 rpm to 1500 rpm, 1500 rpm to 1700 rpm, 1700 rpm to 1900 rpm, or 1800 rpm to 2000 rpm. In some embodiments, the added texture can increase the spin rate under wet conditions by 5% to 30%, more specifically by 5% to 10%, 10% to 15%, 15% to 20%, or 20% to 30%. In some embodiments, the added texture can increase the spin rate by approximately 13.5%. Since dew or other moisture often settles and remains on the grass, encountering wet conditions during golf is a more common occurrence. Therefore, improving spin rate and other performance parameters in wet conditions is particularly important for golfers.

[0083] Increased ball spin improves shot accuracy by helping the golf ball stay near the point of impact with the ground rather than rolling forward. Furthermore, the striking face without the texture described herein tends to induce lower spin rates in wet conditions than in dry conditions. For clubheads with the texture described herein, the induced spin rate may be approximately the same in wet and dry conditions. This similar spin rate between wet and dry conditions improves the golfer's ability to predict their shot distance.

[0084] Furthermore, by texturing the front surface 16 of the striking face, the launch angle of the golf ball in wet conditions can be reduced. In wet conditions, the texture of the front surface of the striking face can reduce the launch angle by 1 to 3 degrees compared to a striking face without the texture described herein. In some embodiments, the texture of the front surface of the striking face can reduce the launch angle by approximately 1 to 1.5 degrees, 1.5 to 2.0 degrees, or 2.5 to 3.0 degrees. Reducing the launch angle can improve shot performance for wedge-type or iron-type clubheads. Additionally, by texturing the front surface 16 of the striking face, the potential ball velocity imparted to the golf ball in wet conditions can be increased. On average, the texture of the front surface of the striking face does not negatively affect ball velocity.

[0085] In some embodiments, the textured or treated surface may have a Vickers hardness (HV) of 70 to 90, 70 to 75, 75 to 80, 80 to 85, 85 to 90, or 75 to 85. The textured or treated surface may have a Vickers hardness (HV) 10 to 20 points higher than that of the untreated surface. In some embodiments, the hardness and fine grain structure of the multiple depressions can reduce crack initiation and slow crack propagation on the front surface of the striking face. In other words, the potential ball velocity achievable with an untextured striking face is maintained after the front surface 16 of the striking face is texturized.

[0086] As described above, the textured or treated surface of a golf club head can exhibit different coefficients of friction, material grain structure, hardness, and / or residual stress compared to an untreated surface. One or more of the front surface, back surface, and / or sole surface (i.e., the treated surface) can have a fine grain structure. The laser impact surface patterning process, which creates depressions on the surface to be treated, can alter the grain structure of the material. When the surface to be treated undergoes a micro-forging process, dislocations or voids at the grain boundaries are permanently compressed. This results in a finer grain structure than the original. The finer grain structure gives the treated surface resistance to crack initiation and crack propagation because the voids at the grain boundaries are compressed. In other words, forging depressions on the striking face can increase the fatigue resistance of the face, allowing the club head to withstand more impacts from the golf ball before it breaks.

[0087] A textured or treated surface may have compressive residual stress. In embodiments having a treated striking face rear surface, the compressive stress generated by the micro-forged depressions can offset the tensile stress applied to the rear surface during impact. This offset of tensile stress allows the striking face to be more durable and to store impact energy better.

[0088] The LSSP process can also be used to relieve stress within the weld zone. To create a complete golf club head, the striking face is often welded to the club head body. The resulting weld zone, or heat-affected zone (HAZ), contains stressed metal material that is more prone to failure than adjacent metal components. LSSP treatment of the weld zone or HAZ can improve durability by relieving stress within the welded metal material. Laser impact surface patterning processes micro-forge the surface being treated, thereby altering the surface's texture, hardness, and material grain structure.

[0089] Finally, the aerodynamic properties of a treated surface can be improved by texturing one or more surfaces of a golf club head using LSSP. Using texturing to obtain aerodynamic benefits is particularly useful for the crown surface and / or sole surface. The modified surface structure created by LSSP can improve the laminar airflow over the surface. By improving the laminar airflow over the crown and / or sole surface, the total drag on the club head can be reduced, increasing swing speed and consequently increasing ball speed. method

[0090] Referring to Figure 10, the above method for manufacturing a striking face includes: providing a golf club head having a striking face, which in some embodiments includes: providing a striking face (step 150); placing a mask layer on the front surface of the striking face and applying an absorption layer (or ablation layer) above the mask layer (step 152); placing a confinement layer above the absorption layer (step 154); forging an array or portion of an array of depressions by focusing a laser beam above a spot on the striking face and applying a laser impact to the absorption layer (step 156); removing the confinement layer and mask layer by repeating steps 154 and 156 with the laser aimed at an untreated spot on the striking face until a desired portion of the front surface of the striking face is processed (step 158); and cleaning the striking face if necessary. For the purposes of the following discussion, the reference numbers used above for the golf club head 10 will also be used in the description of this method. However, the method for manufacturing a striking face is not limited to a specific wedge-type golf club head 10.

[0091] In step 150 of the process, providing the striking face 12 may include casting, forging, pressing, 3D printing, or otherwise forming the striking face 12. The laser impact surface patterning (LSSP) process requires that the portion of the front surface to be treated be flat or level. Therefore, step 100 may further include grinding, polishing, lapping, or otherwise forming at least one flat area on the front surface 16. For some golf club heads, the entire striking face front surface 16 is ground, polished, lapped, or otherwise formed to be flat or level. The flatter the surface, the more efficient the LSSP process becomes.

[0092] In step 152, a mask layer 140 is positioned above the front surface 16 of the striking face. In some embodiments, the mask layer 140 may be a mesh such as a metal mesh or wire cloth. The mask layer 140 may also be called a protective mold layer or mesh layer. The mask layer 140 may have apertures corresponding to the desired occupancy shape of the depression 100 created by the laser impact forging (LSSP) process. The mask layer 140 may be graded by the number of apertures per linear inch. The mask 140 may be a 400 mesh, having 400 equally spaced apertures per inch. In other embodiments, the mask 140 may be 200 mesh, 225 mesh, 250 mesh, 275 mesh, 300 mesh, 325 mesh, 350 mesh, 375 mesh, 400 mesh, 425 mesh, 450 mesh, 475 mesh, 500 mesh, 525 mesh, 550 mesh, 575 mesh, 600 mesh, 625 mesh, 650 mesh, 675 mesh, or 700 mesh. In some embodiments, several separate mask layers are used to form different recess patterns on different parts of the striking face 12.

[0093] In step 154, an absorption layer 142 is applied above the mask layer 140. The absorption layer 142 may also be called a plasma generation layer or ablation layer. The material forming the absorption layer 142 must be carbon-based and be black or very dark in color. In some embodiments, the absorption layer material is graphite, graphene, or any other suitable carbon-based material. In some embodiments, the absorption layer 142 may be a tape. The absorption layer 142 can be applied to the mask layer 140 by tape application, spraying, coating, injection, laying, or other means. In some embodiments having a tape-type absorption layer 142, the tape can be used to hold the mask layer 140 in place. The absorption layer 142 absorbs energy from the laser beam 146, converting the material of the absorption layer 142 into a plasma state. The color of the carbon-based material causes the material to absorb the energy transmitted by the laser beam 146 applied in step 156.

[0094] In embodiments where graphene is used as the material for the absorption layer 142, the uniform geometric shape of the graphene platelets allows for more efficient absorption of laser energy than other carbon materials. Due to its structure, graphene may have a larger surface area exposed to the laser beam 156 compared to other carbon materials. In some embodiments, the absorption material is a spray (or adhesive paint), while in other embodiments, the material is a powder. The material for the absorption layer 142 can be provided as particles of various sizes. The size of the absorption layer particles can affect the power of the resulting shock wave. For example, larger particles can generate more plasma, resulting in a higher-power shock wave, while smaller particles result in a lower-power shock wave. The absorption layer 142 may further contain air or other trace elements trapped within the main material of the layer.

[0095] In step 154, a containment layer 144 is placed above the absorbent layer 142. The containment layer 144 is formed of a transparent, airtight material. In some embodiments, the containment layer 144 is water. In other embodiments, the containment layer 144 is a glass plate. The glass plate must be flat to ensure an airtight seal to the absorbent material 142. If the containment layer 144 is water, the absorbent material 142 may be a non-washable spray, tape, or adhesive paint (powder is easily washed away). If the containment layer 144 is a glass plate, the containment layer 144 is preferably a powder.

[0096] In step 156, the laser beam 146 is focused above a spot on the front surface 16 of the striking face. The energy from the laser beam 146 is transferred into the absorption layer 142 via a transparent confinement layer 144 (water in this example). When the laser 146 strikes the absorption layer 142, the absorption layer is ablated and then ionized. The laser shock converts the absorption layer 142 into a plasma state. This generates a shock wave 148 that impacts the surface below. The shock wave 148 presents rapid changes in the pressure, temperature, and density of the absorption layer 142. The mask layer 140 prevents the plasma from affecting the mesh-covered portion of the front surface 16 of the striking face. However, the aperture of the mask layer 140 allows the plasma shock wave 148 to reach the exposed microsurface portions through the aperture. The shock wave 148 forges these exposed microsurface portions to form depressions 100. A single pulse of laser 146 can forge multiple depressions 100 through plasma generation caused by the shock wave 148.

[0097] The size of the laser beam 146 does not determine the size of the depression 100. Rather, the size of the depression 100 is determined by the mask layer 140. The depression 100 corresponds to the size of the aperture of the mask layer 140. By using the mask layer 140, it is possible to adjust the depression size to a desired size to produce a desired texture or roughness on the front surface 16 of the striking face. The texture of the front surface 16 then determines the coefficient of the striking face 12.

[0098] As described above, the light intensity of the laser beam 146 can affect the coefficient of friction. In some embodiments, increasing the light intensity of the laser beam 146 can increase the coefficient of friction. However, in some embodiments, it is also possible to first decrease the coefficient of friction compared to an untreated striking face. Furthermore, the light intensity of the laser beam 146 can also affect the hardness of the striking face. In some embodiments, and for some striking face materials, the hardness of the striking face 12 can be increased by using a higher laser beam intensity.

[0099] The process of applying laser impact treatment (LSSP) to the surface can be repeated until the laser impact treatment is applied to all areas of the striking face 12 where texturing is desired. In some embodiments, the entire striking surface 16 is texturized. In some embodiments, only a portion of the striking face front surface 16 is texturized. Because the size of the laser beam 146 is small compared to the striking face 12, it is necessary to repeat this process. In some embodiments of this method, the step 156 of applying laser impact to a small surface area can be repeated between 300 and 400 times to texturize the entire striking face front surface 16.

[0100] Each laser impact 148 covers approximately a 3x3mm grid (0.09cm²). 2(This covers the area) and can be completed between 3 nanoseconds and 25 nanoseconds. Further accounting for the time required to apply the containment layer 144, the absorption layer 142, and the mask layer 140, each depression 100 can be created between 0.4 microseconds and 0.8 microseconds. In some embodiments, each depression can be created in 0.6 microseconds. Compared to a slower method lacking the mask layer 140, the high speed of forging the depressions 100 enables the rapid production of the striking face 12.

[0101] In some embodiments, the surface being processed is a curved surface. The laser impact surface patterning (LSSP) process requires a flat surface at least across the entire local processing area. Therefore, a curved surface can be processed by dividing the surface into a plurality of locally flat surface regions. These flat regions allow for the local application of multiple depressions through the laser impact surface patterning process.

[0102] In step 158, the containment layer 144 and the mask layer 140 are removed from the striking face 12. In some embodiments, this requires the draining of water from the absorption layer 142. The treated surface can be cleaned after the laser impact treatment (LSSP) is complete. Any residue remaining after removing the absorption layer 142 can be removed from the striking face 12 by wiping or other means.

[0103] The above method may be called indirect laser impact processing (or indirect laser impact surface patterning). In some embodiments, the method for producing a golf club head as described herein includes a direct laser impact processing method. In the direct laser impact processing method, a mask layer 140 is placed on an absorption layer 142 to shield the absorption layer 142 from the laser beam 146. In an alternative embodiment of the method for forming the striking face disclosed herein, laser impact processing (LSSP) can be applied to a metal sheet, and then the striking face 12 can be cut out from the metal sheet.

[0104] A method for manufacturing the rear surface of the striking face, the sole surface, and / or the crown surface includes steps similar to those for processing the front surface 16 of the striking face. A manufacturing method for producing a golf club head having one or more processed surfaces may include: providing the golf club head body to provide the striking face; placing a mask layer on the surface to be processed; applying an absorption layer above the mask layer; placing a containment layer above the absorption layer; forging a recess array or a portion of a recess array by focusing a laser beam over a spot on the surface to be processed and laser-impacting the absorption layer; repeating the laser-impact process by aiming the laser at an unprocessed spot on the surface until a desired portion of the surface is processed; removing the containment layer and mold layer; and cleaning the surface if necessary. This method can be applied to the rear surface of the striking face, the sole surface, and / or the crown surface. In some embodiments, one or more of the front surface of the striking face, the rear surface of the striking face, the sole surface, and / or the crown surface are processed two or more times according to this manufacturing method. By treating the surface two or more times, it is possible to change the shape of the depressions, increase the surface hardness, and / or change the depth of the depressions. Production equipment

[0105] The manufacture of the striking face 12 having the texture described herein may require a production apparatus. Typically, the production apparatus includes means for holding the striking face 12, the crown insert, the sole insert, and / or the golf club head body with the crown and sole. The production apparatus further includes a casing for holding and / or surrounding the mask layer 140, the absorbent layer 142, and the containment layer 144.

[0106] In some manufacturing scenarios, sourcing a mask layer (or mesh) the size of the impact face can be costly for creating depressions with a width of 1.2 μm or less. Therefore, to reduce production costs, a smaller mesh, commonly known as a TEM grid, can be used instead of a mask layer the size of the impact face. TEM grids are readily available and affordable on the market because they are commonly used in transmission electron microscopy.

[0107] In some embodiments, the production apparatus may include a base plate for holding the club head, a frame, and a plurality of pins (not shown) for removably securing the frame to the base plate. The frame can slide when the plurality of pins are not in position. Figures 11 and 12 illustrate production apparatus 200, which operates in the same manner as production apparatus having means for holding the club head, but lacks means for holding the club head. The frame 230 rests on the base plate 210. The frame 230 houses the TEM grid. The frame 230 is secured to the base plate 210 in either a first or second position. Figure 12 shows the frame 230 in the second position. In the first position, the frame 230 can be positioned slightly higher than in the second position. The position of the frame 230 controls which area of ​​the striking face is treated, because the frame 230 determines where the laser impact surface treatment is applied.

[0108] Referring to Figures 11 and 12, the base plate 210 comprises an upper surface 212, a bottom surface (not shown), means for clamping the golf club head (not shown), a plurality of holes 218 for receiving fastening members, and a plurality of pin holes 222, 224 for receiving pins. In some embodiments, a gap (not shown) is formed in the upper surface 212. The gap is shaped to hold the golf club head with the striking face facing upward. The striking face can be positioned parallel to the upper surface 212.

[0109] The base plate 210 itself can be secured to the laser table via a plurality of holes 218 and fastening members (not shown). In some embodiments, clamps or other fastening mechanisms are used to hold the golf club head in the gap. In some embodiments, the upper surface 212 of the base plate 210 is provided with two passages 228 that engage with the frame 230, allowing the frame 230 to slide from a first position to a second position. In other embodiments, the upper surface 212 of the base plate lacks the passages 228. In these embodiments, the frame 230 can be lifted and moved from the first position to the second position.

[0110] The frame 230 has an upper surface 232 and a bottom surface (not shown). Typically, the frame 230 is formed from a thick metal plate. The frame 230 has a plurality of apertures 238 sized to receive the TEM grid. The plurality of apertures 238 are aligned across the entire frame 230. Each aperture extends from the upper surface 232 to the bottom surface through the frame 230. Each aperture may have a certain diameter. The apertures 238 can be spaced apart by a distance less than the diameter of the aperture. The plurality of apertures 238 may include between 40 and 80 apertures. In some embodiments, the plurality of apertures 238 include 40, 45, 50, 55, 60, 65, 70, 75, or 80 apertures.

[0111] The frame 230 is further provided with clamp tabs 236. The clamp tabs 236 extend outward from two or more sides of the frame 230. The clamp tabs 236 allow the frame 230 to be secured to the worktable and / or base plate 210. Securing the frame 230 is important for maintaining a watertight seal between the base plate 210 and the frame 230. A watertight seal is necessary because deionized water is often used as a containment layer.

[0112] The frame 230 further has a plurality of pin holes 240 for receiving pins. When the frame 230 is in the first position, at least one of the base plate pin holes 222, 224 corresponds to at least one of the frame pin holes 240. When the frame 230 is positioned in the second position, different base plate pin holes 222, 224 correspond to different frame pin holes 240. In this configuration, when the frame is in the first position, only the first set of pin holes 222 is used, and in the second position, only the second set of pin holes 224 is used. This allows the operator to easily identify the position of the frame. At least one pin is positioned through at least one pin hole to properly align and hold the frame 230 in either the first or second position.

[0113] One exemplary method of using the production apparatus 200 may first involve bolting a base plate 210 onto a laser table. The golf club head is secured to the base plate 210. The frame 230 is positioned above the base plate 210 and the striking face of the club head. The frame 230 is positioned on the base plate 210 in a first position. The frame 230 is clamped onto the base plate 210 and the striking face. Multiple TEM grids (acting as mask layers) are inserted into multiple apertures 238 of the frame 230. The TEM grids are coated by filling the multiple apertures 238 with carbon powder or graphene powder (acting as an absorption layer). The multiple apertures 238 are further filled with deionized water (acting as a confinement layer). An Nd-YAG laser is emitted through each of the multiple apertures 238 to peen (or forge) the portion of the striking face below each aperture.

[0114] The frame 230 is removed or cleaned. The frame 230 is placed on the base plate 210 in a second position. The process of preparing and processing the face is repeated at the second location. Because the frame 230 has been shifted, a new area of ​​the face is processed. In this manner, a large portion of the striking face surface area can be processed in a time-efficient and cost-effective manner. Examples Example 1 - Robot Testing

[0115] A golf club head of an embodiment having a textured striking face front surface was compared with a control standard golf club head having a striking face front surface lacking the texture. The golf club head of the embodiment was a wedge type with a loft angle of 58 degrees. The golf club head of the embodiment had a striking face and body similar to the golf club head 10 described above. The golf club head of the embodiment was made of 8620 alloy steel. The striking face had a front surface with multiple depressions.

[0116] In the club head of the embodiment, the depressions on the surface in front of the striking face were shaped like squares. Each of the multiple depressions occupied an area of ​​approximately 1369 μm². 2 (0.00000225in 2 The recesses were approximately 37 μm (0.0015 inches) wide, 37 μm (0.0015 inches) high, and had a maximum depth of approximately 600 μm (0.0232 inches). The multiple recesses were organized into rows. When the golf club head was in the address position, these rows were oriented horizontally (heel-toe). Each recess was spaced approximately 37 μm (0.0015 inches) apart from each adjacent recess. By using the LSSP process, the multiple recesses were formed within the striking face of the golf club head of the embodiment. The control standard golf club head was identical to the golf club head of the embodiment, except that this control standard lacked the multiple recesses on the front surface of the striking face.

[0117] Multiple depressions were applied in groups, where each group of depressions was organized into a circular shape with a diameter of 2 mm (similar to the pocket region 62 described above). Each group of depressions had a duration of 7 ns and an energy density of 1 GW / cm². 2 The texture was fabricated using a single laser pulse. The groups of depressions were arranged adjacent to each other in the heel-toe direction, with a distance of approximately 0.1 mm between the edges of each circular depression, each having a diameter of 2 mm. The groups of depressions could not overlap. Therefore, achieving the minimum separation distance between groups was essential for covering the surface with the LSSP texture / depressions.

[0118] Three performance parameters—launch angle, ball speed, and ball spin—were tested. Each parameter was tested in both dry and wet conditions. In the wet condition tests, both the ball and club head were exposed to moisture before each test shot. Comparisons were made using a robot programmed to swing the golf club in the same manner for each shot. Fifteen shots were hit in dry conditions and fifteen shots in wet conditions. Below, the data is presented as the average of these 15-shot sets. In addition, the statistical area corresponding to where the shot stopped was measured for both clubs to illustrate the potential shot accuracy of each test club.

[0119] As illustrated in the graph in Figure 13, under dry conditions, the launch angle of the club head in the example was nearly comparable to that of the control standard club head. In this test, the launch angle was approximately 31.5 degrees for the control standard and approximately 31.4 degrees for the club head in the example, with an error bar of approximately 0.2 degrees. However, under wet conditions, the launch angle of the club head in the example was approximately 2.2 degrees lower than that of the control standard club head, with an error bar of approximately 0.7 degrees. The launch angle was approximately 33.1 degrees for the control standard and approximately 30.9 degrees for the club head in the example. The lower the launch angle of the club head in the example, the more accurately the ball can be traversed. As the wind strength increases with height above the ground, a lower launch angle reduces the time the golf ball is exposed to windy conditions at high altitudes. As the data above shows, the club head in the example exhibited a launch angle in wet conditions that was close to its own launch angle in dry conditions. This similarity in performance across multiple conditions provides greater consistency for golfers, allowing them to better predict shot performance.

[0120] As illustrated in the graph in Figure 14, under dry conditions, the amount of spin imparted to the golf ball by the clubhead in the example was comparable to the amount of spin imparted by the control standard clubhead. In this test, the average spin rate under dry conditions was approximately 10,222 rpm for the control standard and 10,206 rpm for the clubhead in the example, with an error bar between 100 rpm and 300 rpm. Under wet conditions, the amount of spin imparted by the clubhead in the example was significantly higher than that imparted by the control standard clubhead. Under wet conditions, the clubhead in the example imparted an average spin rate of approximately 10,578 rpm, with an error bar of approximately 500 rpm. Under wet conditions, the control standard clubhead imparted an average spin rate of approximately 9,316 rpm. Therefore, under wet conditions, the clubhead in the example imparted approximately 13.5% faster spin than the control standard clubhead. This faster spin rate helps the golf ball stop closer to where the shot first impacted the ground. Reducing spin reduces the ball's roll after landing, which improves shot accuracy.

[0121] Furthermore, the spin rate data also shows that the club head in the embodiment has a more consistent spin rate across dry and wet conditions than the control standard club head. For the control standard club head, the average spin rate differs by approximately 906 rpm between dry and wet conditions. For the club head in the embodiment, the average spin rate differs by approximately 372 rpm between dry and wet conditions. Therefore, because the average spin rate of the club head in the embodiment differs less between dry and wet conditions, golfers can predict shot performance better when using the club head in the embodiment.

[0122] As illustrated in the graph in Figure 15, the ball velocity imparted by the clubhead in the embodiment was slightly lower in dry conditions and slightly higher in wet conditions compared to the control standard clubhead. Therefore, the ball velocity was more consistent across multiple conditions. In dry conditions, the ball velocity imparted by the control standard clubhead was approximately 76.2 mph, with an error bar of approximately 0.3 mph. In dry conditions, the ball velocity imparted by the clubhead in the embodiment was approximately 75.8 mph, with an error bar of approximately 0.3 mph. In wet conditions, the ball velocity of the clubhead in the embodiment was approximately 75.1 mph, with an error bar of approximately 0.4 mph. The ball velocity of the control standard clubhead was approximately 74.8 mph, with an error bar of approximately 0.6 mph. This data indicates that, considering the overall performance of the clubhead, the texture on the striking face of the clubhead in the embodiment does not have a significant negative or positive impact on ball velocity.

[0123] The plot in Figure 16 shows the statistical area determined by where the test shots landed. Shots hit with the clubhead of the embodiment were approximately twice as accurate as shots hit with the control standard clubhead. The statistical area for the control standard clubhead was approximately 18 square yards, while the statistical area for the clubhead of the embodiment was approximately 7 square yards. Shots hit with the control standard clubhead had a carry of approximately 85 to 92 yards and a downline variance of approximately 7 yards. Shots hit with the clubhead of the embodiment had a carry of approximately 87 to 90 yards and a downline variance of approximately 3 yards. Additionally, the clubhead of the embodiment also exhibited smaller offline (left or right) variance than the control standard clubhead.

[0124] This comparative test further showed that when the striking face was textured using the LSSP process, the coefficient of friction between the front surface of the striking face and the urethane golf ball increased by approximately 40% to 45% under wet conditions. In other words, the striking face of the club head in the example showed a coefficient of friction 40% to 45% higher than that of the striking face of the control standard club head.

[0125] In summary, the clubheads in the examples exhibited a lower launch angle, higher spin rate, and a larger golf ball-to-face friction coefficient compared to the control standard clubhead. These factors result in greater accuracy for the golfer regarding their shots. This study further demonstrated this increase in shot accuracy through the plotting of statistical areas. Example 2 - Prospective Player Test

[0126] A prospective player test comparison will be conducted between an embodiment golf club head having a textured striking face front surface and a control standard golf club head having a striking face front surface without the texture. For this comparison test, 15 to 20 golfers will hit shots using the test golf clubs. The embodiment golf club head is a wedge-type golf club head identical to the embodiment golf club head in Embodiment 1 above. Briefly, the embodiment golf club head has a striking face front surface with multiple square-shaped depressions, each of which occupies an area of ​​approximately 1369 μm². 2 (0.00000225in 2 The surface has a maximum depth of approximately 600 μm (0.0232 inches). Multiple recesses are formed through the LSSP process. The control standard golf club head is identical to the golf club head of the embodiment, except that this control standard lacks multiple recesses on the surface in front of the striking face.

[0127] Three performance parameters—launch angle, ball speed, and ball spin—will be tested. Each parameter will be tested under realistic wet conditions. Shots will be hit from turf maintained to match the fairway conditions of a golf course. Each golfer will hit a total of 10 shots with each club, alternating between a golf club with the embodiment head and a golf club with a control standard head every 5 shots. For both clubs, the statistical area corresponding to where these shots stop will also be measured to illustrate the potential shot accuracy of each test club. The coefficient of friction between the striking face and the urethane golf ball will be calculated from the launch angle and ball spin results.

[0128] The launch angle of the club head in this embodiment is expected to be approximately 2 degrees lower than that of the control standard club head. The lower the launch angle of the club head in this embodiment, the more accurately the ball is expected to travel.

[0129] The amount of spin imparted by the club head in the embodiment is expected to be significantly higher than that imparted by the control standard club head. The club head in the embodiment is expected to impart an average spin rate approximately 1,000 rpm higher than that of the control standard club head. The club head in the embodiment is expected to impart a spin rate approximately 10% to 20% faster than that imparted by the control standard club head. This faster spin rate helps the golf ball stop closer to where it first impacts the ground, thereby improving shot accuracy.

[0130] The ball speed is expected to be between 70 and 80 mph. The ball speed imparted by the clubhead in the example is expected to be approximately 0.5 mph higher than the ball speed imparted by the control standard clubhead. The statistical area is determined by where the test shot lands. Shots hit with the clubhead in the example are expected to be more than twice as accurate as shots hit with the control standard clubhead. Additionally, the clubhead in the example is expected to exhibit less offline (left or right) variance than the control standard clubhead.

[0131] Furthermore, the club head striking face of the embodiment is expected to exhibit a coefficient of friction 40% to 45% higher than that of the control standard club head striking face (based on a urethane-coated golf ball). In summary, the club head of the embodiment is expected to exhibit a lower launch angle, higher spin rate, and a larger golf ball-to-striking face friction coefficient than the control standard club head. This test is also expected to demonstrate an increase in shot accuracy by texturing the striking face using LSSP. Example 3 - Laser light intensity vs. depression depth

[0132] To demonstrate the correlation between laser light intensity and depression depth, prospective experiments are conducted. Table I below shows several expected maximum depression depths for a given laser light intensity. [Table 1] Approximately 0.484GW / cm 2 When the impact face is processed using an LSSP process with a laser light intensity of approximately 0.554 GW / cm², a maximum indentation depth of approximately 0.2 μm is expected. 2 When the impact face is treated using an LSSP process with a laser light intensity of approximately 0.778 GW / cm², a maximum indentation depth of approximately 0.5 μm is expected. 2When the impact face is processed using an LSSP process with a laser light intensity of approximately 0.890 GW / cm², a maximum indentation depth of approximately 0.8 μm is expected. 2 When the impact face is treated using an LSSP process with a laser light intensity of approximately 575 GW / cm², a maximum indentation depth of approximately 0.9 μm is expected to result. 2 When the impact face is treated using an LSSP process with a laser light intensity of approximately 1920 GW / cm², a maximum indentation depth of approximately 4.9 μm is expected to result. 2 When the impact face is treated using an LSSP process with a laser light intensity, a maximum indentation depth of approximately 15 μm is expected to result. As outlined by these prospective results, this experiment is expected to demonstrate that increasing the laser light intensity also leads to an increase in the maximum indentation depth.

[0133] The results of this prospective experiment are expected to be similar to those of the experiment recorded in the publication Mao, Bo & Siddaiah, Arpith & Menezes, Pradeep & Liao, Yiliang (2018). "Surface Texturing by indirect laser shock surface patterning for manipulated friction coefficient," Journal of Materials Processing Tech. vol.257(2018) pp.227-233). This publication by Mao et al. teaches that as the laser light intensity increases, the resulting depression depth can increase. In Mao et al.'s experiment, the depression depth increased from approximately 0.2 μm to approximately 0.9 μm as the laser light intensity increased from approximately 0.5 GW / cm2 to approximately 0.9 GW / cm2.

[0134] Because the rules of golf can change from time to time (for example, new rules may be adopted or old rules may be abolished or modified by golf standards bodies and / or governing bodies), golf equipment related to the methods, apparatus, and / or products described herein may be compliant or non-compliant with the rules of golf at any given time. Therefore, golf equipment related to the methods, apparatus, and / or products described herein may be advertised, marketed, and / or sold as compliant or non-compliant golf equipment. The methods, apparatus, and / or products described herein are not limited in this respect.

[0135] While a specific order of operations has been described above, these operations may be performed in other temporal sequences. For example, two or more of the above operations may be performed sequentially, in parallel, or simultaneously. Alternatively, two or more operations may be performed in reverse order. Furthermore, one or more of the above operations may be omitted entirely. The apparatus, methods, and products described herein are not limited in this respect.

[0136] Having described this invention in various aspects, it will be understood that further modifications of this invention are possible. This application generally adheres to the principles of this invention and is intended to cover all modifications, uses, or applications of this invention, including deviations from this disclosure that are known and customary within the art to which this invention belongs. item

[0137] Item 1: A golf club head comprising a body having a heel end and a toe end, and a striking face having a geometric center, wherein the striking face has a front surface, the front surface has a plurality of depressions, each of the plurality of depressions has a center point, one or more side walls, and a bottom surface, and each depression has an occupied area measured as an area surrounded by the side walls in a plane coinciding with the front surface, the occupied area is 0.01 μm2 From 250,000 μm 2 A golf club head, wherein each recess has a maximum depth from the bottom surface to a surface coinciding with the front surface, measured perpendicular to the front surface, and the maximum depth is between 0.1 μm and 15 μm, and each recess has a width measured in the heel-toe direction through the center point of the recess, and the width is between 0.1 μm and 500 μm.

[0138] Item 2: The golf club head according to Item 1, wherein each recess has a height measured in the sole-top rail direction through the center point of the recess, and the height is between 0.1 μm and 500 μm.

[0139] Item 3: The golf club head according to Item 1, wherein the coefficient of friction between the front surface and the urethane-coated golf ball is between 0.05 and 0.95.

[0140] Item 4: The golf club head described in Item 1, wherein the area occupied by each recess has a shape selected from the group consisting of a square shape, a triangular shape, a rectangular shape, a circular shape, and a hexagonal shape.

[0141] Item 5: The golf club head according to Item 1, wherein the one or more side walls include a number of side walls selected from the group consisting of 1-sided side walls, 2-sided side walls, 3-sided side walls, 4-sided side walls, 5-sided side walls, 6-sided side walls, 7-sided side walls, 8-sided side walls, 9-sided side walls, and 10-sided side walls.

[0142] Item 6: The golf club head according to Item 1, wherein the plurality of recesses cover 30% to 60% of the front surface.

[0143] Item 7: The golf club head of Item 1, wherein the plurality of recesses cover between 60% and 100% of the front surface.

[0144] Item 8: The occupied area is 500 μm 2 From 100,000 μm 2The golf club head described in item 1 is between the above.

[0145] Item 9: Any of the above-mentioned depressions is 1 μm to 250 μm (approximately 3.9 × 10) from the adjacent depression. -5 Golf club heads as described in Item 1, spaced apart by a separation distance of approximately 0.0098 inches.

[0146] Item 10: The golf club head described in Item 1, wherein the multiple indentations increase the amount of golf ball spin by 5% to 30% in wet conditions.

[0147] Item 11: The golf club head described in Item 1, wherein the multiple depressions increase the launch angle by 1 to 3 degrees under wet conditions.

[0148] Item 12: A golf club head comprising a body having a heel end and a toe end, The device comprises a striking face having a geometric center, the striking face having a front surface, the front surface comprising a recess array having a plurality of recess rows aligned parallel to the array axis, each recess having a center point, one or more side walls, and a bottom surface, and each recess having an occupied area measured as the area enclosed by the side walls in a plane coinciding with the front surface, the occupied area being 0.01 μm 2 From 250,000 μm 2 A golf club head, wherein each recess has a maximum depth from the bottom surface to a surface coinciding with the front surface, measured perpendicular to the front surface, and the maximum depth is between 0.1 μm and 15 μm, and each recess has a width measured parallel to the array axis through the center point of the recess, and the width is between 0.1 μm and 500 μm.

[0149] Item 13: The golf club head according to Item 12, wherein the golf club head further has a horizontal reference axis extending from the heel end to the toe end through the geometric center of the striking face, and the recessed array is angled such that the array axis intersects the horizontal reference axis at an angle of plus or minus 0 to 90 degrees.

[0150] Item 14: The golf club head according to Item 13, wherein the recessed array is angled such that the array axis intersects the horizontal reference axis at an angle selected from the group consisting of plus or minus 10 degrees, plus or minus 20 degrees, plus or minus 30 degrees, plus or minus 40 degrees, plus or minus 45 degrees, plus or minus 50 degrees, plus or minus 60 degrees, plus or minus 70 degrees, plus or minus 80 degrees, and 90 degrees.

[0151] Item 15: The golf club head according to Item 12, further comprising a horizontal reference axis, a low region, and a high region, wherein the horizontal reference axis extends from the heel end to the toe end through the geometric center of the striking face, the low region is below the horizontal reference axis, the high region is above the horizontal reference axis, and the majority of the recess array is located within the low region.

[0152] Item 16: The golf club head according to Item 12, wherein the coefficient of friction between the front surface and the urethane-coated golf ball is between 0.05 and 0.95.

[0153] Item 17: The golf club head according to Item 12, wherein the recessed array has an array length measured in the direction from the heel end to the toe end, and the array length is between 1.5 inches and 2.5 inches.

[0154] Item 18: A golf club head comprising a body and a striking face, wherein the striking face has a front surface, and the front surface comprises a recess array having a plurality of recessed rows aligned parallel to the array axis, each recess having a center point, one or more side walls, and a bottom surface, and each recess has an occupied area measured as the area enclosed by the side walls in a plane coinciding with the front surface, and the occupied area is 0.01 μm 2 From 250,000 μm 2 A golf club head, wherein each recess has a maximum depth measured perpendicular to the front surface from the bottom surface to a surface coinciding with the front surface, each recess has a width measured parallel to the array axis through the center point of the recess, each recess has an aspect ratio equal to the maximum depth divided by the width, and the aspect ratio is between 3 and 150.

[0155] Item 19: The golf club head described in Item 18, wherein the aspect ratio is between 75 and 125.

[0156] Item 20: The golf club head described in Item 18, wherein the aspect ratio is between 50 and 100.

Claims

1. It is a golf club head, A main body having a heel end and a toe end, A striking face having a geometric center, It is equipped with, The striking face has a front surface, The aforementioned front surface has a plurality of depressions, Each of the aforementioned plurality of depressions has a center point, one or more side walls, and a bottom surface. Each recess has an occupied area that is measured as an area enclosed by the side walls within a plane that coincides with the front surface. The occupied area is 0.01 μm ２ From 250,000 μm ２ It is between, Each depression has a maximum depth measured perpendicular to the front surface, from the bottom surface to the surface coinciding with the front surface. The aforementioned maximum depth is between 0.1 μm and 15 μm. Each recess has a width that is measured in the heel-toe direction through the center point of the recess. The width is between 0.1 μm and 500 μm. Golf club head.

2. Each recess has a height that is measured in the sole-top rail direction through the center point of the recess. The aforementioned height is between 0.1 μm and 500 μm. The golf club head according to claim 1.

3. The golf club head according to claim 1, wherein the coefficient of friction between the front surface and the urethane-coated golf ball is between 0.05 and 0.

95.

4. The golf club head according to claim 1, wherein the area occupied by each recess has a shape selected from the group consisting of a square shape, a triangular shape, a rectangular shape, a circular shape, and a hexagonal shape.

5. The golf club head according to claim 1, wherein the one or more side walls include a number of side walls selected from the group consisting of one-sided side walls, two-sided side walls, three-sided side walls, four-sided side walls, five-sided side walls, six-sided side walls, seven-sided side walls, eight-sided side walls, nine-sided side walls, and ten-sided side walls.

6. The golf club head according to claim 1, wherein the plurality of recesses cover 30% to 60% of the front surface.

7. The golf club head according to claim 1, wherein the plurality of recesses cover 60% to 100% of the front surface.

8. The occupied area is 500 μm ２ From 100,000 μm ２ A golf club head according to claim 1, which is between [a certain range].

9. Each of the aforementioned depressions is located 1 μm to 250 μm (approximately 3.9 × 10) from the adjacent depression. －５ The golf club heads according to claim 1, which are spaced apart by a separation distance between an inch and approximately 0.0098 inches.

10. The golf club head according to claim 1, wherein the plurality of depressions increase the amount of golf ball spin by 5% to 30% under wet conditions.

11. The golf club head according to claim 1, wherein the plurality of depressions increase the launch angle by 1 to 3 degrees under wet conditions.

12. It is a golf club head, A main body having a heel end and a toe end, A striking face having a geometric center, It is equipped with, The striking face has a front surface, The aforementioned front surface comprises a recess array having a plurality of recessed rows aligned parallel to the array axis, Each depression has a central point, one or more side walls, and a bottom surface. Each recess has an occupied area that is measured as an area enclosed by the side walls within a plane that coincides with the front surface. The occupied area is 0.01 μm ２ From 250,000 μm ２ It is between, Each depression has a maximum depth measured perpendicular to the front surface, from the bottom surface to the surface coinciding with the front surface. The aforementioned maximum depth is between 0.1 μm and 15 μm. Each depression has a width that is measured parallel to the array axis, passing through the center point of the depression. The width is between 0.1 μm and 500 μm. Golf club head.

13. The golf club head further has a horizontal reference axis that extends from the heel end to the toe end, passing through the geometric center of the striking face. The recessed array is angled such that the array axis intersects the horizontal reference axis at an angle of 0 to 90 degrees, either plus or minus 0 degrees. The golf club head according to claim 12.

14. The golf club head according to claim 13, wherein the recessed array is angled such that the array axis intersects the horizontal reference axis at an angle selected from the group consisting of plus or minus 10 degrees, plus or minus 20 degrees, plus or minus 30 degrees, plus or minus 40 degrees, plus or minus 45 degrees, plus or minus 50 degrees, plus or minus 60 degrees, plus or minus 70 degrees, plus or minus 80 degrees, and 90 degrees.

15. The aforementioned golf club head further has a horizontal reference axis, a low region, and a high region. The horizontal reference axis extends from the heel end to the toe end, passing through the geometric center of the striking face. The low region is below the horizontal reference axis, The aforementioned high region is above the aforementioned horizontal reference axis, Most of the recess array is located within the low region. The golf club head according to claim 12.

16. The golf club head according to claim 12, wherein the coefficient of friction between the front surface and the urethane-coated golf ball is between 0.05 and 0.

95.

17. The recess array has an array length measured in the direction from the heel end to the toe end, The array length is between 1.5 inches and 2.5 inches. The golf club head according to claim 12.

18. It is a golf club head, The main unit and The hitting face and, It is equipped with, The striking face has a front surface, The aforementioned front surface comprises a recess array having a plurality of recessed rows aligned parallel to the array axis, Each depression has a central point, one or more side walls, and a bottom surface. Each recess has an occupied area that is measured as an area enclosed by the side walls within a plane that coincides with the front surface. The occupied area is from 0.01 μm ２ to 250,000 μm ２ and is in the range of Each depression has a maximum depth measured perpendicular to the front surface, from the bottom surface to the surface coinciding with the front surface. Each depression has a width that is measured parallel to the array axis, passing through the center point of the depression. Each depression has an aspect ratio equal to the maximum depth divided by the width. The aspect ratio is between 3 and 150. Golf club head.

19. The golf club head according to claim 18, wherein the aspect ratio is between 75 and 125.

20. The golf club head according to claim 18, wherein the aspect ratio is between 50 and 100.

Images