Golf club head with localized heat affected zone

Abstract

To provide a golf club head having a localized heat treatment.SOLUTION: A golf club head, and in particular, a wood-type golf club head including a faceplate having one or plural heat affected parts (HAZ) to enable a consistent or a reasonable tolerance error variation in CT over the entire faceplate is disclosed. The heat affected part can be formed via weld beads that locally alter a specific part, a portion, or a region of the faceplate without entirely altering the characteristics and properties of the faceplate all at once. Locally altering the specific part or the region of the faceplate via weld beads (or spot welds) to form a heat affected part can alter a microstructure of that region or the part.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates generally to golf clubs, and more particularly to golf club heads having one or more localized heat affected zones (HAZ).

[0002] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 62 / 900,378, filed September 13, 2019, the entire contents of which are incorporated herein by reference in their entirety. [Background technology]

[0003] Characteristic time (CT) is a measurement of the amount of time, in microseconds, that a golf ball is in contact with the face plate during impact. The characteristic time requirement is one of many rules imposed by the United States Golf Association (USGA) and the Royal and American Golf Association (R&A) on golf equipment manufacturers to determine the conformance of a club head. Often, the characteristic time characteristics of a golf club head are not uniform but vary substantially across the face plate. This variation can result in inconsistencies in club head performance and, more specifically, can generate different ball velocities depending on where ball impact occurs on the face plate. These small changes in the location of ball impact across the face plate can lead to noticeable changes in generated ball velocities and ball flight distances, thereby making the game unpredictable for golfers.

[0004] Changes in golf club head characteristics over time can be brought about by face plates with asymmetrical perimeter shapes and / or variable face plate characteristics (i.e., thickness, material, texture, face-to-body transition, etc.). Reducing the thickness of the material used to form the golf club head, and more specifically the face plate, can be beneficial for many reasons. Among these reasons are that a thinner face plate can reduce weight, increase flexibility, and reduce the amount of material used. By reducing weight in certain areas of the golf club head, that weight can be redistributed (as needed) to improve club head performance.

[0005] Redistributing weight from the face plate can result in increased flexibility and increased energy transfer to the golf ball. This increased flexibility (resulting from a thinner face plate) can result in more variable CT across the face plate. There is a need in the art for a repeatable, efficient, and affordable manufacturing method that allows for localized modification of CT to reduce CT variation across the face plate. [Brief explanation of the drawings]

[0006] [Figure 1] 1 shows a front view of a golf club head in an address position. [Figure 2] 1 shows a front view of a golf club head in the address position with CT reference measurement locations. [Figure 3] 1 shows a front view of a golf club head having a rectangular reference shape in an address position. [Figure 4] 1 shows a front view of a golf club head having an oval reference shape in an address position. [Figure 5] 1 illustrates a front view of a golf club head having a multi-linear reference shape at address position. [Figure 6]1 illustrates a front view of a golf club head having an oval reference shape and one or more HAZs in an address position. [Figure 7] 1 illustrates a front view of a golf club head in an address position, the golf club head having a linear reference shape and one or more HAZs. [Figure 8] 1 illustrates a front view of a golf club head having a rectangular reference shape and one or more HAZs in an address position. [Figure 9] 1 illustrates some structural aspects of an exemplary structure and / or embodiment of a HAZ. [Figure 10] 1 is a schematic diagram of a process for forming a golf club head assembly. [Figure 11] 1 is a chart comparing ball speeds (in miles per hour) for a test club with a HAZ, a control club without a HAZ, and a 1 degree lofted control club without a HAZ. [Figure 12] 10 is a chart comparing launch angles for a test club with a HAZ, a control club without a HAZ, and a control club with a loft of 1 degree and no HAZ. [Figure 13] 1 is a chart comparing spin rates (rpm) for a test club with a HAZ, a control club without a HAZ, and a control club with a 1-degree loft that does not have a HAZ.

[0007] Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings.

[0008] For simplicity and clarity of illustration, the drawings show general types of structures, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the present disclosure. Further, elements in the drawings are not necessarily drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help improve understanding of embodiments of the present disclosure. The same reference numbers in different drawings represent the same elements. DETAILED DESCRIPTION OF THE INVENTION

[0009] Presented herein is a golf club head, particularly a wood-type golf club head, with a face plate having one or more heat-affected zones (HAZ) to allow for consistent or reasonable tolerance variation in CT across the face plate. The heat-affected zone may be formed via a weld bead that locally modifies a particular portion, section, or region of the face plate without collectively altering the features and characteristics of the face plate as a whole. The local modification of a particular portion or region of the face plate via a weld bead (or spot weld) to form a heat-affected zone may alter the microstructure of that region or region. The microstructural modification in the targeted region or region may alter the characteristic time characteristics of that region or region when impacted by a golf ball.

[0010] Because the characteristic time characteristics vary across the face plate in both the heel-toe and crown-sole directions, the areas of the face plate targeted for heat treatment and / or HAZ may be areas that approximate characteristic time thresholds to avoid the golf club head having hot spots (i.e., portions of the face plate that are at, near, or close to USGA and R&A CT limits), areas of the club head that potentially have non-compliant CT due to manufacturing variations, and / or specific areas of the face plate that fall out of compliance with repeated club head use and wear. As a result of a face plate with localized heat-affected zone treatment (via weld beads or spot welds), the treated areas may have different material properties (i.e., different microstructures to alter the CT) than non-heat-affected areas of the same material. These portions, regions, or portions targeted for conditioning may generally be defined by a reference shape. Furthermore, methods for manufacturing the golf club heads described herein are outlined below.

[0011] The terms "first," "second," "third," "fourth," and the like in the specification and claims, when present, are used to distinguish between similar elements and do not necessarily describe a particular order or chronological sequence. Terms so used should be understood to be interchangeable under appropriate circumstances, such that the embodiments described herein are operable, for example, in orders other than those illustrated or otherwise described herein. Furthermore, the terms "include" and "have," and any variations thereof, are intended to include non-exclusive inclusions, such that a process, method, system, article, device, or apparatus that includes a list of elements is not necessarily limited to those elements and may include other elements not expressly listed or inherent to such process, method, system, article, device, or apparatus.

[0012] Terms such as "left," "right," "front," "rear," "top," "bottom," "above," "below," and the like in the specification and claims, when present, are used for descriptive purposes and do not necessarily describe permanent relative positions. Terms so used should be understood to be interchangeable under appropriate circumstances, such that, for example, embodiments of the apparatus, methods, and / or articles of manufacture described herein are operable in orientations other than those illustrated or otherwise described herein.

[0013] The term "driver-type golf club head" as described herein may be defined by one or more of loft angle, club head volume, club head weight, or club head material.

[0014] 1.Loft angle In many embodiments, the loft angle of the driver-type club head may be less than about 16 degrees, less than about 15 degrees, less than about 14 degrees, less than about 13 degrees, less than about 12 degrees, less than about 11 degrees, less than about 10 degrees, less than about 9 degrees, less than about 8 degrees, or less than about 7 degrees.

[0015] 2. Volume Furthermore, in many embodiments, the volume of the driver-type club head may be greater than about 400 cc, greater than about 425 cc, greater than about 450 cc, greater than about 475 cc, greater than about 500 cc, greater than about 525 cc, greater than about 550 cc, greater than about 575 cc, greater than about 600 cc, greater than about 625 cc, greater than about 650 cc, greater than about 675 cc, or greater than about 700 cc. In some embodiments, the volume of the driver-type club head may be between about 400 cc and 600 cc, between about 425 cc and about 500 cc, between about 500 cc and about 600 cc, between about 500 cc and about 650 cc, between about 550 cc and about 700 cc, between about 600 cc and about 650 cc, between about 600 cc and about 700 cc, or between about 600 cc and about 800 cc.

[0016] 3. Weight In some embodiments, the driver-type club head may have a weight (or mass) of 170 grams to 250 grams. In other embodiments, the driver-type club head may have a weight (or mass) of 170 grams to 175 grams, 175 grams to 180 grams, 180 grams to 185 grams, 185 grams to 190 grams, 190 grams to 195 grams, 195 grams to 200 grams, 200 grams to 205 grams, 205 grams to 210 grams, 210 grams to 215 grams, 215 grams to 220 grams, 220 grams to 225 grams, 225 grams to 230 grams, 230 grams to 235 grams, 235 grams to 240 grams, 240 grams to 245 grams, or 245 grams to 250 grams. In some embodiments, the weight of a driver-type club head is 170 grams, 171 grams, 172 grams, 173 grams, 174 grams, 175 grams, 176 grams, 177 grams, 178 grams, 179 grams, 180 grams, 181 grams, 182 grams, 183 grams, 184 grams, 185 grams, 186 grams, 187 grams, 188 grams, 189 grams, 190 grams, 191 grams, 192 grams, 193 grams, 194 grams, 195 grams, 196 grams, 197 grams, 198 grams, 199 grams, 200 grams, 201 grams, 202 grams, 203 grams, 204 grams, 205 grams, 206 grams, 207 grams, 208 grams, 209 grams, 300 grams, 310 grams, 311 grams, 312 grams, 313 grams, 314 grams, 315 grams, 316 grams, 317 grams, 318 grams, 319 grams, 320 grams, 321 grams, 322 grams, 323 grams, 324 grams, 325 grams, 326 grams, 327 grams, 328 grams, 329 grams, 330 grams, 331 grams, 332 grams, 333 grams, 334 grams, 335 grams, 336 grams, 337 grams, 338 grams, 339 grams, 340 grams, 341 grams, 342 grams, 343 grams, 344 grams, 345 grams, 346 grams, 347 grams, 348 grams, 349 grams, 350 grams, 351 grams 09 grams, 210 grams, 211 grams, 212 grams, 213 grams, 214 grams, 215 grams, 216 grams, 217 grams, 218 grams, 219 grams, 220 grams, 221 grams, 222 grams, 223 grams, 224 grams, 225 grams, 226 grams, 227 grams, 228 grams, 229 grams, 230 grams, 231 grams, 232 grams, 233 grams, 234 grams, 235 grams, 236 grams, 237 grams, 238 grams, 239 grams, 240 grams, 241 grams, 242 grams, 243 grams, 244 grams, 245 grams, 246 grams, 247 grams, 248 grams, 249 grams, or 250 grams.

[0017] 4.Material The material of the driver-type golf club head may be constructed from any material used to construct conventional golf club heads. For example, the material of the driver-type golf club head may be constructed from any one or combination of the following: 8620 alloy steel, S25C steel, carbon steel, maraging steel, 17-4 stainless steel, 1380 stainless steel, 303 stainless steel, stainless steel alloy, steel alloy, tungsten, aluminum, aluminum alloy, ADC-12, titanium, titanium alloy, or any other known metal or composite material for making driver-type golf club heads. In many embodiments, the driver-type golf club head may be constructed from titanium and / or composite materials.

[0018] The term "fairway wood-type golf club head" as used herein may be defined by one or more of loft angle, club head volume, club head weight, or club head material.

[0019] 1.Loft angle In many embodiments, the loft angle of a fairway wood-type club head may be less than about 35 degrees, less than about 34 degrees, less than about 33 degrees, less than about 32 degrees, less than about 31 degrees, or less than about 30 degrees. Additionally, in many embodiments, the loft angle of the club head may be greater than about 12 degrees, greater than about 13 degrees, greater than about 14 degrees, greater than about 15 degrees, greater than about 16 degrees, greater than about 17 degrees, greater than about 18 degrees, greater than about 19 degrees, or greater than about 20 degrees. For example, in some embodiments, the loft angle of a fairway wood-type club head may be between 12 and 35 degrees, between 15 and 35 degrees, between 20 and 35 degrees, or between 12 and 30 degrees.

[0020] 2. Volume In many embodiments, the volume of a fairway wood-type club head may be less than about 400 cc, less than about 375 cc, less than about 350 cc, less than about 325 cc, less than about 300 cc, less than about 275 cc, less than about 250 cc, less than about 225 cc, or less than about 200 cc. In some embodiments, the volume of the club head may be between about 150 cc and 200 cc, between about 150 cc and 250 cc, between about 150 cc and 300 cc, between about 150 cc and 350 cc, between about 150 cc and 400 cc, between about 300 cc and 400 cc, between about 325 cc and 400 cc, between about 350 cc and 400 cc, between about 250 cc and 400 cc, between about 250 cc and 350 cc, or between about 275 cc and 375 cc.

[0021] 3. Weight In many embodiments, a fairway wood-type club head may have a weight between 170 grams and 215 grams. In other embodiments, a fairway wood-type golf club head may weigh between 170 grams and 175 grams, 175 grams and 180 grams, 180 grams and 185 grams, 185 grams and 190 grams, 190 grams and 195 grams, 195 grams and 200 grams, 200 grams and 205 grams, 205 grams and 210 grams, or 210 grams and 215 grams. In some embodiments, the weight of a fairway wood-type club head may be 170 grams, 171 grams, 172 grams, 173 grams, 174 grams, 175 grams, 176 grams, 177 grams, 178 grams, 179 grams, 180 grams, 181 grams, 182 grams, 183 grams, 184 grams, 185 grams, 186 grams, 187 grams, 188 grams, 189 grams, 190 grams, 191 grams, 192 grams, 193 grams, 194 grams, 195 grams, 196 grams, 197 grams, 198 grams, 199 grams, 200 grams, 201 grams, 202 grams, 203 grams, 204 grams, 205 grams, 206 grams, 207 grams, 208 grams, 209 grams, 210 grams, 211 grams, 212 grams, 213 grams, 214 grams, or 215 grams.

[0022] 4.Material The material of the fairway wood-type golf club head may be constructed from any material used to construct conventional golf club heads. For example, the material of the fairway wood-type golf club head may be constructed from any one or combination of the following: 8620 alloy steel, S25C steel, carbon steel, maraging steel, 17-4 stainless steel, 1380 stainless steel, 303 stainless steel, stainless steel alloy, steel alloy, tungsten, aluminum, aluminum alloy, ADC-12, titanium, titanium alloy, steel alloy, or any other known metal or composite material for making fairway wood-type golf club heads. In many embodiments, the fairway wood-type golf club head is constructed from titanium and / or composite materials.

[0023] The term "hybrid golf club head" as described herein may be defined by one or more of loft angle, club head volume, club head weight, or club head material.

[0024] 5.Loft angle In many embodiments, the loft angle of the hybrid-type golf club head may be less than about 40 degrees, less than about 39 degrees, less than about 38 degrees, less than about 37 degrees, less than about 36 degrees, less than about 35 degrees, less than about 34 degrees, less than about 33 degrees, less than about 32 degrees, less than about 31 degrees, or less than about 30 degrees. Additionally, in many embodiments, the loft angle of the hybrid-type club head may be greater than about 16 degrees, greater than about 17 degrees, greater than about 18 degrees, greater than about 19 degrees, greater than about 20 degrees, greater than about 21 degrees, greater than about 22 degrees, greater than about 23 degrees, greater than about 24 degrees, or greater than about 25 degrees.

[0025] 6. Volume In many embodiments, the hybrid-type club head volume may be less than about 200 cc, less than about 175 cc, less than about 150 cc, less than about 125 cc, less than about 100 cc, or less than about 75 cc. In some embodiments, the club head volume may be between about 100 cc and 150 cc, between about 75 cc and 150 cc, between about 100 cc and 125 cc, or between about 75 cc and 125 cc.

[0026] 7. Weight In many embodiments, the hybrid-type club head may have a weight between 190 grams and 240 grams. In other embodiments, the hybrid-type golf club head may weigh between 190 grams and 195 grams, 195 grams and 200 grams, 200 grams and 205 grams, 205 grams and 210 grams, 210 grams and 215 grams, 215 grams and 220 grams, 220 grams and 225 grams, 225 grams and 230 grams, 230 grams and 235 grams, or 235 grams and 240 grams. In some embodiments, the weight of the hybrid club head is 190 grams, 191 grams, 192 grams, 193 grams, 194 grams, 195 grams, 196 grams, 197 grams, 198 grams, 199 grams, 200 grams, 201 grams, 202 grams, 203 grams, 204 grams, 205 grams, 206 grams, 207 grams, 208 grams, 209 grams, 210 grams, 211 grams, 212 grams, 213 grams, It may be 214 grams, 215 grams, 216 grams, 217 grams, 218 grams, 219 grams, 220 grams, 221 grams, 222 grams, 223 grams, 224 grams, 225 grams, 226 grams, 227 grams, 228 grams, 229 grams, 230 grams, 231 grams, 232 grams, 233 grams, 234 grams, 235 grams, 236 grams, 237 grams, 238 grams, 239 grams, or 240 grams.

[0027] 8.Materials The materials of the hybrid golf club head may be constructed from any material used to construct a conventional golf club head. For example, the materials of the hybrid golf club head may be constructed from any one or combination of the following: 8620 alloy steel, S25C steel, carbon steel, maraging steel, 17-4 stainless steel, 1380 stainless steel, 303 stainless steel, stainless steel alloy, steel alloy, tungsten, aluminum, aluminum alloy, ADC-12, titanium, titanium alloy, steel alloy, or any other known metal or composite for making a hybrid golf club head. In many embodiments, the hybrid golf club head may be constructed from a titanium alloy and / or composite material.

[0028] The term "spot welding" as described herein may be defined as the application of a weld bead to a material at a specific location to create a heat affected zone that changes the physical grain structure from an equiaxed circular microstructure to a dendritic microstructure, where the material microstructure transforms back to the equiaxed circular microstructure upon removal from the spot weld.

[0029] Before describing any embodiments of the present disclosure in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or carried out in various ways.

[0030] Described below is a golf club head with a reference shape to help provide a consistent CT across the face plate. The reference shape includes a heat-affected zone (HAZ) that provides the ability to reduce / limit CT characteristics in specific regions, thereby producing a CT that is within a predetermined tolerance across the face. More specifically, described herein is a golf club head, particularly a golf club head (driver, fairway wood, or hybrid) with a face plate having at least one heat-affected zone (HAZ) to enable a consistent (or within a predetermined tolerance) CT across the face plate of the golf club head. As described above, the heat-affected zone may be formed via a spot weld or weld bead that alters a specific portion, section, or region of the face plate without collectively altering the features and characteristics of the face plate as a whole. The localized alteration of a specific portion or region of the face plate (via a spot weld or weld bead) to form a heat-affected zone may alter the microstructure of that region or section (to a dendritic microstructure) and therefore alter the characteristic time characteristics of the treated location.

[0031] For example, generally, the portions of the golf club head having the greatest characteristic time measurements may typically be found (1) toward the geometric center of the face plate, (2) offset from the geometric center of the face plate toward the toe of the face plate, (3) offset from the geometric center toward the top edge of the face plate, or combinations thereof. These regions may potentially have characteristic time measurements that are at, near, or approximate the CT threshold (i.e., the USGA and R&A CT limit).

[0032] To form a faceplate with a more uniform CT (i.e., no "CT hot spots"), the region of interest for the local heat-affected zone may be characterized by a reference shape. The local heat-affected zone may be formed within or on the periphery of the reference shape via a spot weld or weld bead. The heat-affected zone within the reference shape may have different material properties (i.e., a different (dendritic) microstructure) than the non-heat-affected zone outside the reference shape to locally modify the CT.

[0033] (golf club head) The golf club heads described herein may be driver-type club heads, fairway wood-type golf club heads, or hybrid-type club heads as defined above. In many embodiments, the golf club heads may be wood-type golf club heads (i.e., driver-type golf club heads, fairway wood-type golf club heads, or hybrid-type golf club heads). Driver-type golf club heads, fairway wood-type golf club heads, and hybrid-type golf club heads may be characterized by loft angle, head volume, and / or head weight, as described above.

[0034] In some embodiments, the golf club head may be formed of stainless steel, titanium, aluminum, or a steel alloy (e.g., 455 steel, 475 steel, 431 steel, 17-4 stainless steel, maraging steel), a titanium alloy (e.g., Ti7-4, Ti6-4, T-9S), an aluminum alloy, or a composite material. In some embodiments, the face plate of the golf club head may be formed of stainless steel, titanium, aluminum, or a steel alloy (e.g., 455 steel, 475 steel, 431 steel, 17-4 stainless steel, maraging steel), a titanium alloy (e.g., Ti7-4, Ti6-4, T-9S), an aluminum alloy, or a composite material.

[0035] (Golf Club Head Composition and Setup) In many embodiments, the golf club head 100 includes a club head body 124 (which may also be referred to as a "body"). The club head body 124 defines a toe portion 106, a heel portion 105, a top portion 108, a sole portion 109, a rear portion 125, and a faceplate opening configured to receive the faceplate 102. The faceplate 102 may provide a surface adapted for impact with a golf ball. The rear portion 125 is spaced rearward from the faceplate 102. The sole portion 109 is defined as being between the faceplate 102 and the rear portion 125 and resting on the ground 118 (or playing surface) at address. The top portion 108 may be formed opposite the sole portion 109. The faceplate 102 is defined by the sole portion 109, the top portion 108, the heel portion 105, and the toe portion 106, which is opposite the heel portion 105.

[0036] As previously mentioned, golf club head 100 may be configured to be in the "address position." Unless otherwise noted or stated, golf club head 100 is in the address position for all reference measurements, ratios, and / or descriptive parameters. The address position may be referred to as (1) the sole of the golf club head resting on the ground 118 in contact with and parallel to the playing surface, and (2) the striking surface may be substantially perpendicular to the ground.

[0037] The face plate 102 of the club head 100 defines a geometric center 104. In some embodiments, the geometric center 104 may be located at the geometric center point of the face plate perimeter and the midpoint of the face height. In the same or other examples, the geometric center may also be centered relative to a designed impact area, which may be defined by the area of ​​a groove on the face plate. As an alternative approach, the geometric center of the face plate 102 may be located according to a definition by a golf governing body, such as the United States Golf Association (USGA). For example, the geometric center of the face plate 102 may be determined according to Section 6.1 of the USGA's Procedure for Measuring the Flexibility of a Golf Club Head (USGA-TPX3004, Revision 1.0.0, May 1, 2008) (available at http: / / www.usga.org / equipment / testing / protocols / Procedure-For-Measuring-The-Flexibility-Of-A-Golf-Club-Head / ) ("Flexibility Procedure").

[0038] The club head 100 further defines a loft plane that is tangent to the geometric center 104 of the face plate 102. The face height may be measured parallel to the loft plane between an upper end of the perimeter of the face plate near the crown portion 108 and a lower end of the perimeter of the face plate near the sole portion 109. In these embodiments, the perimeter of the face plate 102 may be located along the outer edge of the face plate, where the curvature deviates from the bulge and / or roll of the face plate 102.

[0039] The geometric center 104 of the face plate 102 further defines a coordinate system having an origin located at the geometric center of the face plate 102, the coordinate system having an X'-axis 103, a Y'-axis 107, and a Z'-axis. The X'-axis 103 extends through the geometric center 104 of the face plate 102 in a direction from the heel 105 to the toe 106 of the club head 100. The Y'-axis 107 extends through the geometric center 104 of the face plate 102 in a direction perpendicular to the X'-axis 103 from the crown 108 to the sole 109 of the club head 100, and the Z'-axis extends through the geometric center 104 of the face plate 102 from the front end to the back end of the club head 100 in a direction perpendicular to the X'-axis 103 and the Y'-axis 107.

[0040] The coordinate system defines an X'Y' plane 101 extending through an X' axis 103 and a Y' axis 107. The X'Y' plane 101 extends parallel to a hosel axis (not shown) and is oriented at an angle corresponding to the loft angle of the club head 100 from the loft plane. Additionally, the X' axis 103 may be oriented at a 60 degree angle relative to the hosel axis when viewed from a direction perpendicular to the X'Y' plane. In these or other embodiments, the club head may be viewed from the front ( FIG. 1 ) when viewing the face plate 102 from a direction perpendicular to the X'Y' plane 101.

[0041] When the golf club head 100 is in the address position, the golf club head 100 may be divided into four quadrants (i.e., a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant) bounded by the perimeter of the face plate 102, the X′ axis 103, and the Y′ axis 107. Within one or more quadrants, a reference shape 126 may be projected onto the face plate 102, and the reference shape 126 may include a heat-affected zone (HAZ) to modify areas having characteristic time values ​​generally greater than a characteristic time threshold or target characteristic time. In many embodiments, the reference shape 126 may be bounded or located in its entirety within the first quadrant, the second quadrant, the third quadrant, or the fourth quadrant. In alternative embodiments, the reference shape 126 may extend into one or more quadrants, two or more quadrants, or three or more quadrants. In other embodiments, the reference feature 126 may extend into one or more quadrants along a quadrant boundary (ie, along the X' or Y' axes).

[0042] In most embodiments, one or more HAZs may be located in the high toe quadrant. In some embodiments, one or more HAZs may be located in both the low toe and high toe quadrants. In some embodiments, one or more HAZs may be located in both the high toe and high heel quadrants. In some embodiments, one or more HAZs may be in both the high toe and low heel quadrants. In alternative embodiments, one or more HAZs may be in all quadrants and / or clustered around the geometric center.

[0043] Reference shape 126 may take the form of any shape and preferably does not extend into the body of club head 100 (i.e., is located only on face plate 102). For example, in many embodiments, reference shape 126 may be substantially triangular, square, rectangular, polygonal, semicircular, curvilinear, etc. Generally, the reference shape comprises an area having a characteristic time value that is generally greater than a characteristic time threshold or target characteristic time value.

[0044] One or more characteristic time values ​​on the face plate 102 that are greater than a threshold, designed, or target characteristic time measurement may be detected or located, depending on the manufacturer, through either (1) a standard USGA test method for measuring characteristic time through a thermal probing process (which attempts to identify the location and value of the club head's maximum characteristic time value by taking measurements at strategically selected locations), or (2) by identifying known regions of interest through the aggregation of CT data. Upon detection or identification of regions, areas, and / or locations on the golf club head having characteristic time values ​​that approximate the CT threshold, the given region, area, and / or location on the golf club head may be subjected to or configured with a localized weld bead (or spot weld) to create a heat affected zone (HAZ).

[0045] This produces a face plate 102 with a non-uniform microstructure (see FIGS. 6-9). The CT characteristics of the treated area may be altered by imposing a localized weld bead or spot weld on a given area of ​​interest on the face plate 102 to create a heat-affected zone. In other words, face plate areas (or locations) approaching or exceeding the CT threshold may receive a weld bead or spot weld to create a heat-affected zone that locally alters the microstructure of the treated area to the extent that the CT characteristics of that area decrease according to values ​​below the target CT threshold (to locally create higher strength and / or hardened areas). Thus, instead of modifying the club head contour to accommodate face plate areas with high CT areas (i.e., increasing the face thickness, modifying the face plate's varying face thickness contour, introducing club head strengthening elements, etc.), the applied HAZ structure reduces reliance on bulk (or large-scale) design modifications to the club head and instead focuses on localized changes in the microstructure (or small-scale) modifications to the face plate 102.

[0046] I. Embodiment In many embodiments of the golf club head 100 described below, the heat-affected zone may be found in a specific region of the face plate 102, and further, the heat-affected zone may be bounded or located entirely within the reference shape 126. As discussed above and in detail below, the deposition of a weld bead or spot weld within the reference shape creates a HAZ region that forms a dendritic microstructure (different from non-spot weld regions). In areas where the CT characteristics are equal to or greater than a threshold value, the placement of spot welds at relevant locations results in CT reduction due to dendritic microstructure characteristics. The reference shape may help more easily identify the location of individual CT modifications because it creates a contour around and / or across the area targeted for CT adjustment.

[0047] 1-8 . When viewing the golf club head in a direction generally perpendicular to the X'Y' plane 101 and face plate 102, the golf club head 100 may be defined by a coordinate system having an X' axis 103 extending through the geometric center 104 of the face plate 102 in a heel-to-toe 106 direction, and a Y' axis 107 extending through the geometric center 104 in a top-to-bottom (or crown 108-sole 109) direction.

[0048] The X' axis 103 horizontally divides the golf club head into an upper region 110 and a lower region 111. The upper region 110 of the golf club head is bounded by the X' axis 103, the crown 108, and the maximum heel-toe width of the club head. The lower region 111 of the golf club head is bounded by the X' axis 103, the sole 109, and the maximum heel-toe width of the golf club head. The Y' axis 107 vertically separates the club head into a left region 112 and a right region 113. The left region 112 may be bounded by the Y' axis and the toe end of the golf club head. The right region may be bounded by the Y' axis 107 and the heel 105 of the golf club head 100. Additionally, the X' axis 103 and the Y' axis 107 are perpendicular to each other and form four faceplate quadrant regions.

[0049] Four face plate quadrant areas may be defined as a center-high toe quadrant 114, a center-low toe quadrant 115, a center-high heel quadrant 116, and a center-low heel quadrant 117 when the golf club head is resting on the ground 118 in an address position. The center-high toe quadrant 114 extends from the geometric center 104 and spans the upper left face plate area. The center-low toe quadrant 115 extends from the geometric center 104 and spans the lower left face plate area. The center-high heel quadrant 116 extends from the geometric center 104 and spans the upper right face plate area. The center-low heel quadrant 117 extends from the geometric center 104 and spans the lower right face plate area.

[0050] One or more faceplate quadrant regions 114, 115, 116, 117 may include characteristic time values ​​that are at, exceed, or approximate the characteristic time value of interest. In many embodiments, the quadrant of interest may be the center-high toe quadrant 114, as this region may be identified as a critical region with one or more locations that approximate a critical CT threshold due to manufacturing tolerances and / or variations.

[0051] As shown by FIG. 2, the setup (or address) positions of FIG. 1 and FIG. 2 are similar. FIG. 2 further maps multiple potential location points within the center-high toe quadrant 114 to identify whether the faceplate characteristic time values ​​are at, near, or exceed the characteristic time limits of interest. Generally, CT readings are typically emphasized at the center-high toe because this is the known quadrant of interest. Table 1, provided further in the exemplary section, provides the average approximate CT readings (in microseconds) at corresponding mapped location points on the clubhead within the center-high toe quadrant 114 for each faceplate without a HAZ. In other words, the faceplate 102 of FIG. 2 and Table 1 has a uniform microstructure.

[0052] As further illustrated by FIG. 6 , the first spot weld 119 and second spot weld 120 formed on the faceplate 102 locally alter the microstructure of the faceplate 102 within the heat-affected zone. The microstructure of the heat-affected zone created by the spot welds forms a dendritic structure, a needle-like or finger-like structure that creates smaller grain boundaries to harden or increase faceplate strength in the weld (or HAZ) region. This localized hardening directly correlates with a decrease in the characteristic time of the region where the faceplate's flexibility is limited. The weld pool and locations outside the heat-affected zone (i.e., locations not affected by the spot weld) have a homogenous microstructure with larger grain boundaries relative to the grain boundaries of the heat-affected zone. In many embodiments, the HAZ structure defined by the spot welds produces a faceplate with a 2% to 6% increase in dendritic microstructure compared to a non-spot-welded faceplate.

[0053] As evidenced by the following example, a golf club head having a face plate with a uniform microstructure or non-HAZ structure within the center-high toe quadrant can have characteristic time values ​​that vary by up to 20 μs in the crown-sole and heel-toe directions. Additionally, points measured directly adjacent to another point can vary by up to 16 μs. Having a golf club head with a face plate 102 that has a wide range of characteristic time characteristics depending on the location of golf ball impact can adversely affect the ball velocity generated. In many golf club head embodiments, it is desirable for a given quadrant to have a characteristic time profile that is more uniform (i.e., less variation in the heel-toe and crown-sole directions).

[0054] For identification of quadrants with a high degree of variation and / or meeting or exceeding designed CT parameters, a reference shape may be projected onto the quadrant, more particularly the location of interest, and thus the HAZ. The reference shape may surround or partially encompass the location of interest. As described below, in many embodiments, the reference shape may encompass a large or small area of ​​interest, depending on the CT characteristics of the faceplate 102.

[0055] (rectangular reference shape) In many embodiments, the heat-affected zone may be found in a specific region of the faceplate, and further, the heat-affected zone may be bounded or entirely located within the reference shape. Deposition of a weld bead or spot weld within the reference shape creates a HAZ region that forms a dendritic microstructure (different from non-spot weld areas). In areas where the CT characteristics are equal to or greater than a threshold value, placing spot welds at relevant locations results in CT reduction due to dendritic microstructure characteristics. The reference shape may create a contour around and / or across the area targeted for CT adjustment, thereby helping to more easily identify the location of individual CT modifications.

[0056] 3, in many embodiments, the reference shape 126 encompassing the region of interest (i.e., one or more faceplate CT measurements that meet or exceed the designed CT parameters) may be substantially rectangular. Alternatively, the reference shape 126 may be in the form of a square that may extend from the geometric center 104 of the faceplate 102 to a point within the center-high-tow quadrant 114.

[0057] Rectangular (or square) reference shape 126 may have a height, measured in the loft plane, that extends in the crown-sole direction from about 5% to about 50% of the overall height of face plate 102. In many embodiments, the height of rectangular reference shape 126 may be from about 5% to about 10%, from about 10% to about 15%, from about 15% to about 20%, from about 20% to about 25%, from about 25% to about 30%, from about 30% to about 35%, from about 35% to about 40%, from about 40% to about 45%, or from about 45% to about 50% of the overall height of face plate 102.

[0058] In alternative embodiments, rectangular reference shape 126 may have a maximum height, measured in the loft plane in the crown-sole direction, of between about 0 inches and 1.05 inches. In many embodiments, the maximum height of rectangular reference shape 126 may be between about 0 inches and about 0.25 inches, between about 0.25 inches and about 0.5 inches, between about 0.5 inches and about 0.75 inches, between about 0.75 inches and 1.00 inches, or between about 1.00 inches and about 1.05 inches. In other embodiments, the maximum height of rectangular reference shape may be greater than about 0 inches, greater than about 0.25 inches, greater than about 0.5 inches, greater than about 0.75 inches, or greater than about 1 inch. In alternative embodiments, the maximum height of rectangular reference shape may be less than about 1.05 inches, less than about 1.0 inch, less than about 0.75 inches, less than about 0.5 inches, or less than about 0.25 inches.

[0059] Rectangular (or square) reference shape 126 may have a width, measured in the loft plane, in the heel-toe direction that is between about 5% and about 25% of the overall width of face plate 102. In many embodiments, the width of rectangular reference shape 126 may be between about 5% and about 10%, between about 10% and about 15%, between about 15% and about 20%, or between about 20% and about 25% of the overall width of face plate 102.

[0060] In alternative embodiments, the rectangular reference shape 126 may have a maximum width, measured in the loft plane in the heel-toe direction, of between about 0 inches and 1.05 inches. In many embodiments, the maximum width of the rectangular reference shape 126 may be between about 0 inches and about 0.25 inches, between about 0.25 inches and about 0.5 inches, between about 0.5 inches and about 0.75 inches, between about 0.75 inches and 1.00 inches, or between about 1.00 inches and about 1.05 inches. In other embodiments, the maximum width of the rectangular reference shape 126 may be greater than about 0 inches, greater than about 0.25 inches, greater than about 0.5 inches, greater than about 0.75 inches, or greater than about 1 inch. In alternative embodiments, the maximum width of the rectangular reference shape 126 may be less than about 1.05 inches, less than about 1.0 inch, less than about 0.75 inches, less than about 0.5 inches, or less than about 0.25 inches.

[0061] (elliptical reference shape) As described above, the heat-affected zone may be found in a particular region of the faceplate 102, and further, the heat-affected zone may be bounded or entirely located within the reference shape 126. The deposition of a weld bead or spot weld within the reference shape creates a HAZ region that forms a dendritic microstructure (different from non-spot weld regions). In areas where the CT characteristics are equal to or greater than a threshold value, placing spot welds at relevant locations results in CT reduction due to dendritic microstructure characteristics. The reference shape 126 may create a contour around and / or across the area targeted for CT adjustment, thereby helping to more easily identify the location of individual CT modifications.

[0062] 4, in many embodiments, the reference shape 126 encompassing the area of ​​interest for applying the HAZ region (i.e., one or more faceplate CT measurements that meet or exceed the designed CT parameters) may be substantially elliptical. The reference shape 126, more particularly the elliptical reference shape 126, may extend from the geometric center 104 of the faceplate 102 to a point within the center-high toe quadrant 114.

[0063] An exemplary elliptical reference shape may have a minor axis 127 measured in the loft plane and passing through the center of the ellipse, which may be about 5% to about 50% of the overall height of the faceplate 102. In many embodiments, the minor axis of the elliptical reference shape 126 may be about 5% to about 10%, about 10% to about 15%, about 15% to about 20%, about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, or about 45% to about 50% of the overall height of the faceplate 102.

[0064] In alternative embodiments, the elliptical reference shape 126 may have a minor axis 127 measured in the loft plane between about 0 inches and 1.05 inches. In many embodiments, the minor axis 127 of the elliptical reference shape 126 may measure between about 0 inches and about 0.25 inches, between about 0.25 inches and about 0.5 inches, between about 0.5 inches and about 0.75 inches, between about 0.75 inches and 1.00 inches, or between about 1.00 inches and about 1.05 inches. In other embodiments, the minor axis 127 of the elliptical reference shape may be greater than about 0 inches, greater than about 0.25 inches, greater than about 0.5 inches, greater than about 0.75 inches, or greater than about 1 inch. In alternative embodiments, the minor axis 127 of the elliptical reference shape may be less than about 1.05 inches, less than about 1.0 inch, less than about 0.75 inch, less than about 0.5 inch, or less than about 0.25 inch.

[0065] The elliptical reference shape 126 may have a major axis 128 measured in the loft plane that may be about 5% to about 25% of the overall height of the faceplate 102. In many embodiments, the major axis 128 of the elliptical reference shape 126 may be about 5% to about 10%, about 10% to about 15%, about 15% to about 20%, or about 20% to about 25% of the overall height of the faceplate 102.

[0066] In alternative embodiments, the elliptical reference shape 126 may have a major axis 128 measured in the loft plane between about 0 inches and 1.05 inches. In many embodiments, the major axis 128 of the elliptical reference shape 126 may be between about 0 inches and about 0.25 inches, between about 0.25 inches and about 0.5 inches, between about 0.5 inches and about 0.75 inches, between about 0.75 inches and 1.00 inches, or between about 1.00 inches and about 1.05 inches. In other embodiments, the major axis 128 of the elliptical reference shape 126 may be greater than about 0 inches, greater than about 0.25 inches, greater than about 0.5 inches, greater than about 0.75 inches, or greater than about 1 inch. In alternative embodiments, the major axis 128 of the elliptical reference shape 126 may be less than about 1.05 inches, less than about 1.0 inch, less than about 0.75 inch, less than about 0.5 inch, or less than about 0.25 inch.

[0067] In many embodiments, the major axis 128 of the elliptical reference shape 126 may be angled with respect to the x-axis 103. The angle between the major axis 128 of the elliptical reference shape and the x-axis 103 may be between 20 degrees and 80 degrees. In many embodiments, the angle formed between the elliptical reference shape 126 and the x-axis 103 may vary based on the location of interest. In some embodiments, the angle between the major axis and the x-axis may be between about 20 degrees and about 25 degrees, between about 30 degrees and about 35 degrees, between about 35 degrees and about 40 degrees, between about 40 degrees and about 45 degrees, between about 45 degrees and about 50 degrees, between about 50 degrees and about 55 degrees, between about 55 degrees and about 60 degrees, between about 60 degrees and about 65 degrees, between about 65 degrees and about 70 degrees, between about 70 degrees and about 75 degrees, or between about 75 degrees and about 80 degrees. In many embodiments, the angle formed may be about 45 degrees.

[0068] (Linear reference shape) As described above, the heat-affected zone may be found in a particular region of the faceplate, and further, the heat-affected zone may be bounded or entirely located within reference shape 126. The deposition of a weld bead or spot weld within reference shape 126 creates a HAZ region that forms a dendritic microstructure (different from non-spot weld regions). In areas where the CT characteristics are equal to or greater than a threshold value, placing spot welds at relevant locations results in CT reduction due to dendritic microstructure characteristics. The reference shape may create a contour around and / or across the area targeted for CT adjustment, thereby helping to more easily identify the location of individual CT modifications.

[0069] 5, in many embodiments, the reference shape encompassing the region of interest (i.e., one or more faceplate CT measurements that meet or exceed the designed CT parameters) may be substantially linear. The reference shape, more particularly, linear reference shape 126, may extend from the geometric center 104 of the faceplate 102 to a point within the center-high toe quadrant 114. In many embodiments, one or more HAZs (or weld beads) are applied along linear reference shape 126.

[0070] In many embodiments, linear reference feature 126 may be angled with respect to x-axis 103. The angle between linear reference feature 126 and x-axis 103 may be between 20 degrees and 80 degrees. In many embodiments, the angle formed between linear reference feature 126 and x-axis 103 may vary based on the location of interest. In some embodiments, the angle formed between linear reference feature 126 and x-axis 103 may be between about 20 degrees and about 25 degrees, between about 30 degrees and about 35 degrees, between about 35 degrees and about 40 degrees, between about 40 degrees and about 45 degrees, between about 45 degrees and about 50 degrees, between about 50 degrees and about 55 degrees, between about 55 degrees and about 60 degrees, between about 60 degrees and about 65 degrees, between about 65 degrees and about 70 degrees, between about 70 degrees and about 75 degrees, or between about 75 degrees and about 80 degrees. In many embodiments, the angle formed may be about 45 degrees.

[0071] Linear reference feature 126 may have a maximum height, measured in the loft plane, in the crown-sole direction, that is about 5% to about 50% of the overall height of face plate 102. In many embodiments, the height of the line reference feature may be about 5% to about 10%, about 10% to about 15%, about 15% to about 20%, about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, or about 45% to about 50% of the overall height of face plate 102.

[0072] In alternative embodiments, the linear reference shape 126 may have a maximum height, measured in the loft plane in the crown-sole direction, of between about 0 inches and 1.05 inches. In many embodiments, the maximum height of the linear reference shape 126 may be between about 0 inches and about 0.25 inches, between about 0.25 inches and about 0.5 inches, between about 0.5 inches and about 0.75 inches, between about 0.75 inches and 1.00 inches, or between about 1.00 inches and about 1.05 inches. In other embodiments, the maximum height of the linear reference shape 126 may be greater than about 0 inches, greater than about 0.25 inches, greater than about 0.5 inches, greater than about 0.75 inches, or greater than about 1.0 inches. In alternative embodiments, the maximum height of the linear reference shape 126 may be less than about 1.05 inches, less than about 1.0 inches, less than about 0.75 inches, less than about 0.5 inches, or less than about 0.25 inches.

[0073] Linear reference feature 126 may have a greatest width, measured in the loft plane, in the heel-toe direction, that may be about 5% to about 25% of the overall width of face plate 102. In many embodiments, the width of line reference feature 126 may be about 5% to about 10%, about 10% to about 15%, about 15% to about 20%, or about 20% to about 25% of the overall width of face plate 102.

[0074] In alternative embodiments, the linear reference shape 126 may have a maximum width, measured in the loft plane, between about 0 inches and 1.05 inches in the heel-toe direction. In many embodiments, the maximum width of the linear reference shape 126 may be between about 0 inches and about 0.25 inches, between about 0.25 inches and about 0.5 inches, between about 0.5 inches and about 0.75 inches, between about 0.75 inches and 1.00 inches, or between about 1.00 inches and about 1.05 inches. In other embodiments, the maximum width of the linear reference shape 126 may be greater than about 0 inches, greater than about 0.25 inches, greater than about 0.5 inches, greater than about 0.75 inches, or greater than about 1 inch. In alternative embodiments, the maximum width of the linear reference shape 126 may be less than about 1.05 inches, less than about 1.0 inch, less than about 0.75 inches, less than about 0.5 inches, or less than about 0.25 inches.

[0075] As previously mentioned, the reference shape 126 is projected onto the faceplate 102 to create a boundary around the relevant region. These regions of interest are typically those with high CT values, generally found in the center-high tow quadrant 114. Within the center-high tow quadrant 114, and with specific reference to FIG. 2 and Table 1, it can be seen that at a given measurement location (i.e., CT measurement area), CT can vary by up to approximately 15 μs within a 1-inch by 1-inch area. Furthermore, at adjacent faceplate locations, CT can vary by up to 11 μs. This variation can further increase over time with repeated impacts (i.e., wear). To reduce variation within a localized area without affecting adjacent measurement locations, a HAZ may be formed via spot welds and / or weld beads within the reference shape 126 or at the boundary of the reference shape 126.

[0076] (Reference shape with one or more HAZs) As described above, the heat-affected zone may be found in one or more regions of the faceplate, and further, the heat-affected zone may be bounded or entirely located within the reference shape. The deposition of a weld bead or spot weld within the reference shape creates a HAZ region that forms a dendritic microstructure (different from non-spot weld regions). Placing spot welds at relevant locations in areas where the CT characteristics are equal to or greater than a threshold value results in CT reduction due to the dendritic microstructure characteristics. The reference shape may create a contour around and / or across the area targeted for CT adjustment, thereby helping to more easily identify the location of individual CT modifications.

[0077] As described above, the HAZ is a region created by a weld bead that alters the microstructure of the face plate. As shown in FIG. 6 , two spot welds (i.e., the first spot weld may also be referred to as a “first weld bead” and the second spot weld may also be referred to as a “second weld bead”) are formed on the outer surface of the face plate 102. In other words, the first spot weld 119 and the second spot weld 120 may be applied to the (outer) surface of the face plate 102 that directly contacts the golf ball during impact. In other embodiments, the first and second spot welds 119, 120 do not need to be formed / applied to the outer surface of the face plate 102; conversely, the first and second spot welds 119, 120 may be applied to the rear surface of the face plate 102 in an open crown or open sole design (i.e., the body of the golf club head provides access to the interior of the club head). In many embodiments, the first spot weld 119 may be located at the geometric center of the faceplate, and the second spot weld 120 is spaced apart from the geometric center and located solely in the center-high toe quadrant.

[0078] As previously discussed, the one or more spot welds locally affect the microstructure of a particular region on the faceplate 102 without collectively altering the microstructure across the faceplate 102. The one or more spot welds in FIG. 6 may be generally defined by a diameter. The diameter of the one or more spot welds in contact with the faceplate 102 may be between about 0.125 inches and about 0.75 inches. In many embodiments, the diameter of the one or more spot welds may be between about 0.125 inches and about 0.225 inches, between about 0.225 inches and about 0.325 inches, between about 0.325 inches and about 0.425 inches, between about 0.425 inches and about 0.525 inches, between about 0.525 inches and about 0.625 inches, or between about 0.625 inches and about 0.75 inches. In other embodiments, the diameter of the one or more spot welds may be about 0.1 inch, 0.150 inch, 0.2 inch, 0.250 inch, 0.3 inch, 0.350 inch, 0.4 inch, 0.450 inch, 0.5 inch, 0.550 inch, 0.6 inch, 0.650 inch, 0.7 inch, or 0.750 inch. In alternative embodiments, the diameter of the one or more spot welds may be less than about 0.750 inch, less than about 0.7 inch, less than about 0.65 inch, less than 0.6 inch, less than about 0.55 inch, less than about 0.50 inch, less than about 0.45 inch, less than about 0.40 inch, less than about 0.35 inch, less than about 0.30 inch, less than about 0.20 inch, or less than about 0.15 inch.

[0079] The heat-affected zone formed by the spot weld may be about 20% to about 50% of the diameter of the spot weld. In many embodiments, the spot weld may form a heat-affected zone (i.e., the location where the microstructure changes) of about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, or about 45% to about 50% of the diameter of the spot weld. In other embodiments, the spot weld may form a heat-affected zone of less than about 50%, less than about 45%, less than about 40%, less than about 35%, less than about 30%, or less than about 25% of the diameter of the spot weld. The heat-affected zone is an unmelted region of the faceplate 102 where the microstructure has changed as a result of portions of the metal matrix being exposed to high welding temperatures. The remaining area of ​​the spot weld may be defined as the weld pool region (i.e., the area where the faceplate 102 has reached its melting point and may be ready for filler material to be injected), as shown in the example illustrated in FIG. 9. 9 merely illustrates the reference between the weld bead (or spot weld) and the HAZ. The weld bead may be placed on the exterior of the faceplate surface via heating. The bead is removed via finishing techniques (grinding, grinding, polishing, etc.), but the formed HAZ still readily exists within the structure.

[0080] As previously mentioned, FIG. 6 illustrates first and second spot welds 119 and 120 applied to the faceplate 102 to locally alter the microstructure of the faceplate 102 within the heat-affected zone (HAZ). The microstructure of the HAZ created by the spot welds forms a dendritic structure, a needle-like or finger-like structure that creates smaller grain boundaries to harden or increase faceplate strength in the weld (or HAZ) region. This localized hardening directly correlates with a decrease in the characteristic time of the region where the faceplate's flexibility is limited. The weld pool and locations outside the HAZ (i.e., locations not affected by the spot weld) have a homogenous microstructure with larger grain boundaries relative to the HAZ grain boundaries. In many embodiments, the HAZ structure defined by the spot welds produces a faceplate with a 2% to 6% increase in dendritic microstructure compared to a non-spot-welded faceplate.

[0081] In this particular embodiment, the first spot weld 119 and the second spot weld 120 are positioned on and / or within the reference shape 126 described above, are spaced apart, and do not touch each other. In many embodiments, the centers of the first spot weld 119 and the second spot weld 120 are spaced apart by approximately 0.1 inch to 1 inch. For example, in many embodiments, the centers of the first spot weld 119 and the second spot weld 120 may be spaced apart by 0.1 inch, 0.15 inch, 0.2 inch, 0.25 inch, 0.3 inch, 0.35 inch, 0.4 inch, 0.45 inch, 0.5 inch, 0.55 inch, 0.60 inch, 0.65 inch, 0.70 inch, 0.75 inch, 0.80 inch, 0.85 inch, 0.90 inch, 0.95 inch, or 1.0 inch. In other embodiments, the separation distance between the center of the first spot weld and the center of the second spot weld 120 may be less than 1.0 inch, may be less than 0.95 inch, may be less than 0.90 inch, may be less than 0.85 inch, may be less than 0.80 inch, may be less than 0.75 inch, may be less than 0.70 inch, may be less than 0.65 inch, may be less than 0.60 inch, may be less than 0.55 inch, may be less than 0.50 inch, may be less than 0.45 inch, may be less than 0.40 inch, may be less than 0.35 inch, may be less than 0.30 inch, may be less than 0.20 inch, or may be less than 0.150 inch.

[0082] In many embodiments, the second spot weld 120 may be offset from the geometric center along the X-axis and / or toward the tow by up to about 0.84 inches. In alternative embodiments, the second spot weld 120 may be offset from the geometric center along the X-axis and / or toward the tow by up to about 0.01 inches, 0.02 inches, 0.03 inches, 0.04 inches, 0.05 inches, 0.06 inches, 0.07 inches, 0.08 inches, 0.09 inches, 0.10 inches, 0.11 inches, 0.12 inches, 0.13 inches, 0.14 inches, 0.15 inches, 0.16 inches, 0.17 inches, 0.18 inches, 0.19 inches, 0.20 inches, 0.21 inches, 0.22 inches, 0.23 inches, 0.24 inches, 0.25 inches, 0.26 inches, 0.27 inches, 0.28 inches, 0.29 inches, 0.30 inches, 0.31 inches, 0.32 inches, 0.33 inches, 0.34 inches, 0.35 inches, 0.36 inches, 0.37 inches, 0.38 inches, 0.39 inches, 0.40 inches, 0.41 inches, 0.42 inches, 0.43 inches, 0.44 inches, 0.45 inches, 0.46 inches, 0.47 inches, 0.48 inches, 0.49 inches, 0.50 inches, 0.51 inches, 0.52 inches, 0.53 inches, 0.54 inches, 0.55 inches, 0.56 inches, 0.57 inches, 0.58 inches, 0.59 inches, 0.60 inches, 0.61 inches, 0.62 .18", 0.19", 0.20", 0.21", 0.22", 0.23", 0.24", 0.25", 0.26", 0.27", 0.28", 0.29", 0.30", 0.31", 0.32", 0.33", 0.34", 0.35", 0.36", 0.37", 0.38", 0.39", 0.40", 0. 41", 0.42", 0.43", 0.44", 0.45", 0.46", 0.47", 0.48", 0.49", 0.50", 0.51", 0.52", 0.53", 0.54", 0.55", 0.56", 0.57", 0.58", 0.59", 0.60", 0.61", 0.62", 0.63", 0.6 The offset from the geometric center may be 4 inches, 0.65 inches, 0.66 inches, 0.67 inches, 0.68 inches, 0.69 inches, 0.70 inches, 0.71 inches, 0.72 inches, 0.73 inches, 0.74 inches, 0.75 inches, 0.76 inches, 0.77 inches, 0.78 inches, 0.79 inches, 0.80 inches, 0.81 inches, 0.82 inches, 0.83 inches, or 0.84 inches.

[0083] In the same or other embodiments, the second spot weld 120 may be offset from the geometric center by up to about 0.42 inches toward the crown or top edge of the faceplate. The second spot weld 120 may be offset along the Y-axis direction and / or toward the crown by about 0.01 inch, 0.02 inch, 0.03 inch, 0.04 inch, 0.05 inch, 0.06 inch, 0.07 inch, 0.08 inch, 0.09 inch, 0.10 inch, 0.11 inch, 0.12 inch, 0.13 inch, 0.14 inch, 0.15 inch, 0.16 inch, 0.17 inch, 0.18 inch, 0.19 inch, 0.20 inch. The offset from the geometric center may be 0.21 inch, 0.22 inch, 0.23 inch, 0.24 inch, 0.25 inch, 0.26 inch, 0.27 inch, 0.28 inch, 0.29 inch, 0.30 inch, 0.31 inch, 0.32 inch, 0.33 inch, 0.34 inch, 0.35 inch, 0.36 inch, 0.37 inch, 0.38 inch, 0.39 inch, 0.40 inch, 0.41 inch, or 0.42 inch. In many embodiments, the first and second spot welds are spaced apart and do not touch or abut the face-to-body transition region.

[0084] In many embodiments, as shown in FIG. 6, the first spot weld 119 and the second spot weld 120 are collinear with one another. In alternative embodiments, the first spot weld 119 and the second spot weld need not be collinear. Based on the face plate surface area of ​​the club head shown, approximately 0.5% to 1.0% of the face plate surface area may contact a single weld bead. Up to 16.5% of the exterior face plate surface area may contact any one weld.

[0085] (Linear reference shape with one or more HAZs) The heat-affected zone may be found in a specific region of the faceplate, and further, the heat-affected zone may be bounded or entirely located within the reference shape. Deposition of a weld bead or spot weld within the reference shape creates a HAZ region that forms a dendritic microstructure (different from non-spot weld areas). In areas where the CT characteristics are equal to or greater than a threshold value, placing spot welds at relevant locations results in CT reduction due to dendritic microstructure characteristics. The reference shape may create a contour around and / or across the area targeted for CT adjustment, thereby helping to more easily identify the location of individual CT modifications.

[0086] As mentioned above, the HAZ may also be linearly positioned along the reference shape. As mentioned above, the reference shape 126 may be projected onto the faceplate 102, and more specifically, the linear reference shape 126 may be projected onto a plurality of relevant points on the faceplate 102. These relevant points are typically areas with high CT values ​​and may generally be found in the center-high toe quadrant 114. Within the center-high toe quadrant 114, specifically referring to the following example, it can be seen that the CT at a faceplate measurement location (i.e., the CT measurement area) can vary by up to approximately 15 μs within a 1-inch by 1-inch area. Furthermore, at adjacent faceplate locations, the CT can vary by up to 11 μs. This variation can further increase over time with repeated impacts (i.e., wear). To reduce variation within a localized area without affecting adjacent measurement locations, the HAZ may be formed via spot welding and / or weld beads.

[0087] 7 , a plurality of spot welds 121 (i.e., the plurality of spot welds may also be referred to as "plurality of weld beads") are formed on the outer surface of face plate 102. In other words, the plurality of spot welds 121 may be applied to the (outer) surface of face plate 102 that directly contacts the golf ball during impact. In other embodiments, the plurality of spot welds 121 need not be formed / applied to the outer surface of face plate 102; conversely, the plurality of spot welds 121 may be applied to the rear surface of face plate 102 in an open crown or open sole design (i.e., where the body of the golf club head provides access to the interior of the club head).

[0088] In many embodiments, the plurality of spot welds may be referred to as two or more spot welds, three or more spot welds, four or more spot welds, five or more spot welds, six or more spot welds, seven or more spot welds, eight or more spot welds, nine or more spot welds, ten or more spot welds, eleven or more spot welds, or twelve or more spot welds. The plurality of spot welds may generally be formed along a linear reference shape. In some embodiments, due to precision tolerances, the plurality of spot welds may be slightly offset from the linear reference shape 126.

[0089] As previously discussed, the spot welds 121 locally affect the microstructure of specific regions on the faceplate 102 without collectively altering the microstructure across the faceplate 102. The spot welds illustrated by FIG. 7 may generally be defined by a diameter. The diameter of the spot welds 121 in contact with the faceplate 102 may be between about 0.125 inches and about 0.75 inches. In many embodiments, the diameter of the spot welds may be between about 0.125 inches and about 0.225 inches, between about 0.225 inches and about 0.325 inches, between about 0.325 inches and about 0.425 inches, between about 0.425 inches and about 0.525 inches, between about 0.525 inches and about 0.625 inches, or between about 0.625 inches and about 0.75 inches. In other embodiments, the diameter of the plurality of spot welds 121 may be approximately 0.1 inches, 0.150 inches, 0.2 inches, 0.250 inches, 0.3 inches, 0.350 inches, 0.4 inches, 0.450 inches, 0.5 inches, 0.550 inches, 0.6 inches, 0.650 inches, 0.7 inches, or 0.750 inches. In alternative embodiments, the diameter of the plurality of spot welds 121 may be less than approximately 0.750 inches, less than approximately 0.7 inches, less than approximately 0.65 inches, less than approximately 0.6 inches, less than approximately 0.55 inches, less than approximately 0.50 inches, less than approximately 0.45 inches, less than approximately 0.40 inches, less than approximately 0.35 inches, less than approximately 0.30 inches, less than approximately 0.20 inches, or less than approximately 0.15 inches.

[0090] The heat-affected zones formed by the plurality of spot welds 121 may be about 20% to about 50% of the diameter of each of the plurality of spot welds. In many embodiments, the spot welds may form heat-affected zones (i.e., locations where the microstructure changes) of about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, or about 45% to about 50% of the diameter of the spot weld. In other embodiments, the plurality of spot welds 121 may form heat-affected zones of less than about 50%, less than about 45%, less than about 40%, less than about 35%, less than about 30%, or less than about 25% of the diameter of the spot weld. The heat-affected zone is an unmelted region of the faceplate 102 where the microstructure has changed as a result of exposure to high welding temperatures. The remaining area of ​​the spot weld may be defined as the weld pool area (i.e., the area where the faceplate 102 has reached its melting point and may be ready for filler material to be injected), as shown in the example of FIG.

[0091] As further illustrated by FIG. 7 and described above, the multiple spot welds formed on the faceplate 102 locally alter the microstructure of the faceplate 102 within the heat-affected zone. The microstructure of the heat-affected zone resulting from the spot welds forms a dendritic structure, which is a needle-like or finger-like structure that produces smaller grain boundary sizes to harden or increase the strength of the faceplate 102 in the weld (or HAZ) region. This localized hardening directly correlates with a decrease in the characteristic time of the region, where the flexibility of the faceplate is reduced. Locations outside the weld pool and heat-affected zone (i.e., locations not affected by the spot welds) have a homogeneous microstructure with larger grain boundaries relative to the grain boundaries of the heat-affected zone.

[0092] In this particular embodiment, the plurality of spot welds 121 are positioned along a linear reference shape 126, extending from the geometric center 104 of the face plate 102 to a point in the center-high toe quadrant, but not into the body of the club head. In this exemplary embodiment, each of the plurality of spot welds 121 is in contact with or touching another spot weld of the plurality of spot welds. In other embodiments, the plurality of spot welds need not be in contact with or touching another spot weld. In these embodiments, the plurality of spot welds may be spaced approximately 0.1 inch to 1 inch apart from each other. For example, in many embodiments, multiple spot welds may be spaced apart from one another by 0.1 inch, 0.15 inch, 0.2 inch, 0.25 inch, 0.3 inch, 0.35 inch, 0.4 inch, 0.45 inch, 0.5 inch, 0.55 inch, 0.60 inch, 0.65 inch, 0.70 inch, 0.75 inch, 0.80 inch, 0.85 inch, 0.90 inch, 0.95 inch, or 1.0 inch.

[0093] The spot welds of the plurality of spot welds 121 that are furthest from the geometric center (along the X-axis and / or toward the tow) may be spaced apart by up to about 0.84 inches. In alternative embodiments, the furthest spot welds of the plurality of spot welds 121 may be spaced apart by up to about 0.01 inches, 0.02 inches, 0.03 inches, 0.04 inches, 0.05 inches, 0.06 inches, 0.07 inches, 0.08 inches, 0.09 inches, 0.10 inches, 0.11 inches, 0.12 inches, 0.13 inches, 0.14 inches, 0.15 inches, 0.1 6 inch, 0.17 inch, 0.18 inch, 0.19 inch, 0.20 inch, 0.21 inch, 0.22 inch, 0.23 inch, 0.24 inch, 0.25 inch, 0.26 inch, 0.27 inch, 0.28 inch, 0.29 inch, 0.30 inch, 0.31 inch, 0.32 inch, 0.33 inch, 0.34 inch, 0.35 inch, 0.36 inch, 0.37 inch, 0.38 inch, 0.39 inch , 0.40 inch, 0.41 inch, 0.42 inch, 0.43 inch, 0.44 inch, 0.45 inch, 0.46 inch, 0.47 inch, 0.48 inch, 0.49 inch, 0.50 inch, 0.51 inch, 0.52 inch, 0.53 inch, 0.54 inch, 0.55 inch, 0.56 inch, 0.57 inch, 0.58 inch, 0.59 inch, 0.60 inch, 0.61 inch, 0.62 inch, 0.6 The spacing may be 3 inches, 0.64 inches, 0.65 inches, 0.66 inches, 0.67 inches, 0.68 inches, 0.69 inches, 0.70 inches, 0.71 inches, 0.72 inches, 0.73 inches, 0.74 inches, 0.75 inches, 0.76 inches, 0.77 inches, 0.78 inches, 0.79 inches, 0.80 inches, 0.81 inches, 0.82 inches, 0.83 inches, or 0.84 inches from the geometric center.

[0094] In the same or other embodiments, the spot welds 121 furthest from the geometric center along the Y-axis 107 may be spaced a maximum of about 0.42 inches from the geometric center toward the crown or top edge of the faceplate. The furthest spot welds may be spaced a maximum of about 0.01 inches, 0.02 inches, 0.03 inches, 0.04 inches, 0.05 inches, 0.06 inches, 0.07 inches, 0.08 inches, 0.09 inches, 0.10 inches, 0.11 inches, 0.12 inches, 0.13 inches, 0.14 inches, 0.15 inches, 0.16 inches, 0.17 inches, 0.18 inches, 0.19 inches, 0.20 inches along the Y-axis direction and / or toward the crown. The spot welds 121 may be spaced apart from the geometric center by 0.21 inches, 0.22 inches, 0.23 inches, 0.24 inches, 0.25 inches, 0.26 inches, 0.27 inches, 0.28 inches, 0.29 inches, 0.30 inches, 0.31 inches, 0.32 inches, 0.33 inches, 0.34 inches, 0.35 inches, 0.36 inches, 0.37 inches, 0.38 inches, 0.39 inches, 0.40 inches, 0.41 inches, or 0.42 inches. In many embodiments, the plurality of spot welds 121 are spaced apart and do not touch or abut the face-to-body transition region.

[0095] In many embodiments, the multiple spot welds are collinear with one another, as shown in Figure 7. In alternative embodiments, the multiple spot welds need not be collinear, but are slightly offset from a straight reference line (i.e., non-collinear). Based on the face plate surface area of ​​the club head shown in the exemplary embodiment of Figure 7, approximately 0.5% to 1.0% of the face plate surface area may contact a single weld bead. Up to 16.5% of the exterior face plate surface area may contact any one weld.

[0096] (Rectangular reference shape with one or more HAZs) The heat-affected zone may be found in a specific region of the faceplate, and further, the heat-affected zone may be bounded or entirely located within reference shape 126. The deposition of a weld bead or spot weld within reference shape 126 creates a HAZ region that forms a dendritic microstructure (different from non-spot weld regions). In areas where the CT characteristics are equal to or greater than a threshold value, placing spot welds at relevant locations results in CT reduction due to dendritic microstructure characteristics. Reference shape 126 may help more easily identify the location of individual CT modifications because it creates a contour around and / or across the area targeted for CT adjustment.

[0097] As previously mentioned, the reference shape 126 is projected onto the faceplate 102 to create a boundary around the relevant region. These areas of interest are typically those with high CT values ​​and can generally be found in the center-high toe quadrant 114. Within the center-high toe quadrant 114, and with specific reference to FIG. 2 , it can be seen that at a faceplate location (i.e., the CT measurement area), the CT can vary by up to approximately 15 μs within a 1-inch by 1-inch area. Furthermore, at adjacent faceplate locations, the CT can vary by up to 11 μs. This variation can further increase over time with repeated impacts (i.e., wear). To reduce variation within the localized area without affecting adjacent measurement locations, a HAZ may be formed via spot welding and / or weld beads.

[0098] 8 , at least four spot welds (i.e., first spot weld 119, second spot weld 120, third spot weld 122, and fourth spot weld 123, which may also be referred to as a first weld bead, a second weld bead, a third weld bead, and a fourth weld bead, respectively) are formed on the outer surface of face plate 102. In other words, first spot weld 119, second spot weld 120, third spot weld 122, and fourth spot weld 123 may be applied to the (outer) surface of face plate 102 that directly contacts the golf ball during impact. In other embodiments, the first, second, third, and fourth spot welds 119, 120, 122, 123 need not be formed / applied to the outer surface of the face plate 102; conversely, the first, second, third, and fourth spot welds 119, 120, 122, and 123 may be applied to the rear surface of the face plate 102 in an open crown or open sole design (i.e., a golf club head that provides access to the interior of the club head).

[0099] As previously mentioned, spot welds 119, 120, 122, and 123 can locally affect the microstructure of specific regions on faceplate 102 without collectively altering the microstructure across faceplate 102. The four or more spot welds illustrated in FIG. 8 may generally be defined by a diameter. The diameter of the four or more spot welds 119, 120, 122, and 123 in contact with faceplate 102 may be between about 0.125 inches and about 0.75 inches. In many embodiments, the diameter of one or more spot welds may be between about 0.125 inches and about 0.225 inches, between about 0.225 inches and about 0.325 inches, between about 0.325 inches and about 0.425 inches, between about 0.425 inches and about 0.525 inches, between about 0.525 inches and about 0.625 inches, or between about 0.625 inches and about 0.75 inches. In other embodiments, the diameter of the four or more spot welds may be about 0.1 inch, 0.150 inch, 0.2 inch, 0.250 inch, 0.3 inch, 0.350 inch, 0.4 inch, 0.450 inch, 0.5 inch, 0.550 inch, 0.6 inch, 0.650 inch, 0.7 inch, or 0.750 inch. In alternative embodiments, the diameter of the four or more spot welds may be less than about 0.750 inch, less than about 0.7 inch, less than about 0.65 inch, less than 0.6 inch, less than about 0.55 inch, less than about 0.50 inch, less than about 0.45 inch, less than about 0.40 inch, less than about 0.35 inch, less than about 0.30 inch, less than about 0.20 inch, or less than about 0.15 inch.

[0100] The heat-affected zone formed by a single spot weld may be about 20% to about 50% of the diameter of the spot weld. In many embodiments, the spot weld may form a heat-affected zone (i.e., the location where the microstructure changes) of about 20% to about 25%, about 25% to about 30%, about 30% to about 35%, about 35% to about 40%, about 40% to about 45%, or about 45% to about 50% of the diameter of the spot weld. In other embodiments, the spot weld may form a heat-affected zone of less than about 50%, less than about 45%, less than about 40%, less than about 35%, less than about 30%, or less than about 25% of the diameter of the spot weld. The heat-affected zone is an unmelted region of the faceplate 102 that has undergone a microstructural change as a result of exposure to high welding temperatures. The remaining area of ​​the spot weld may be defined as the weld pool region (i.e., the area where the faceplate 102 has reached its melting point and may be ready for filler material to be injected), as shown in the example illustrated in FIG. 9.

[0101] As further illustrated by FIG. 8 , the first spot weld 119, second spot weld 120, third spot weld 122, and fourth spot weld 123 formed on the faceplate 102 locally change the microstructure of the faceplate 102 within the heat-affected zone. The microstructure of the heat-affected zone created by the spot welds forms a dendritic structure, which is a needle-like or finger-like structure that creates smaller grain boundaries to harden or increase strength in the weld (or HAZ) region of the faceplate 102. This localized hardening directly correlates with a decrease in the characteristic time of the region where the flexibility of the faceplate is reduced. Locations outside the weld pool and heat-affected zone (i.e., locations not affected by the spot welds) have a homogeneous microstructure with larger grain boundaries relative to the grain boundaries of the heat-affected zone (i.e., the region with lower stiffness and higher flexibility).

[0102] In this particular embodiment, first spot weld 119, second spot weld 120, third spot weld 122, and fourth spot weld 123 are positioned on and / or within rectangular reference shape 126 at relative locations and may be spaced apart from one another and do not touch one another. In many embodiments, the separation distance between the center of first spot weld 119, the center of second spot weld 120, the center of third spot weld 122, and the center of fourth spot weld 123 may vary. In many embodiments, the separation distance may be between approximately 0.1 inches and 1 inch. For example, in many embodiments, the center of the first spot weld 119 to the center of at least one of the second spot weld 120, the third spot weld 122, and the fourth spot weld 123 may be spaced 0.1 inch, 0.15 inch, 0.2 inch, 0.25 inch, 0.3 inch, 0.35 inch, 0.4 inch, 0.45 inch, 0.5 inch, 0.55 inch, 0.60 inch, 0.65 inch, 0.70 inch, 0.75 inch, 0.80 inch, 0.85 inch, 0.90 inch, 0.95 inch, or 1.0 inch apart. In other embodiments, the separation distance between the center of first spot weld 119 and at least one of the centers of second spot weld 120, third spot weld 122, and fourth spot weld 123 may be less than 1.0 inch, less than 0.95 inch, less than 0.90 inch, less than 0.85 inch, less than 0.80 inch, less than 0.75 inch, less than 0.70 inch, less than 0.65 inch, less than 0.60 inch, less than 0.55 inch, less than 0.50 inch, less than 0.45 inch, less than 0.40 inch, less than 0.35 inch, less than 0.30 inch, less than 0.20 inch, or less than 0.150 inch. In many embodiments, the first, second, third, and fourth spot welds are spaced apart and do not touch or abut the face-to-body transition region.

[0103] In many embodiments, at least two spot welds are collinear with one another, as shown in Figure 8. In the same or alternative embodiments, at least two spot welds are not collinear with one another. Based on the face plate surface area of ​​the club head shown in the example of Figure 8, approximately 0.5% to 1.0% of the face plate surface area may contact a single weld bead. Not more than 16.5% of the exterior face plate surface area may contact any one weld.

[0104] (Manufacturing method) 10 illustrates a process for forming and / or assembling the golf club head 100. In a first step 200, the face plate 102 may be aligned with the body of the golf club head 100. A second step 300 involves welding the face plate 102 to the body of the club head 100. In a third step 400, the club head and face plate may be heated to, above, or below the solvus temperature of the face plate material through a series of melting and / or aging steps. In a fourth step 500, the club head and face plate are air-cooled.

[0105] Once the club head has cooled, the fifth step 600 involves identifying at least one region of interest on the face plate. This region of interest may typically be identified or found by determining the location where the golf ball remains on the face plate at impact for a period longer than the intentionally designed period. The location may be identified or found by (1) the standard USGA test method for measuring characteristic time via a heat-seeking process (which attempts to identify the location and value of the club head's maximum characteristic time value by taking measurements at strategically selected locations), or (2) by identifying a known region of interest through club head aggregation of CT data.

[0106] Once at least one relevant region on the face plate has been identified, spot welding via plasma welding or laser welding may be applied to the relevant at least one region at a predetermined temperature of 500°C to 650°C for a time period ranging from 1 second to 5 seconds, thereby forming a HAZ region. This step 700 may be completed prior to any face plate finishing steps. For example, localized heat treatment may be completed prior to smoothing or texturing processes, coating / aesthetic processes, and thermal polishing processes of the face plate and / or the entire club head.

[0107] Finally, in a seventh step 800, filler material formed by the spot welds may be polished, smoothed, and / or removed from the faceplate to produce a smooth faceplate surface. In other words, excess material on the faceplate as a result of the spot welds may be removed before polishing so that no mass is added to the faceplate. After removal of the spot welds as described above, macroscopically, the faceplate appears unchanged, but microscopically, portions of the faceplate microstructure have been modified to have a dendritic structure.

[0108] Example 1 To analyze the effectiveness of the golf club head embodiments described herein and obtain quantifiable information regarding the club head's characteristic time, ball speed, launch angle, and spin characteristics, a three-club robotic testing experiment was conducted. Specifically, the embodiment of Figure 7 was benchmarked against a control club with no HAZ and a 1-degree lofted control club with no HAZ.

[0109] The golf club head of Figure 7 tested was a driver-type golf club head having a loft angle of approximately 8.95 degrees, a swing weight of D4.2, a total club head weight (grip + shaft + head) of 317.9 grams, and a finished head weight of 204.5 grams. The control club was a driver-type golf club head having a loft angle of approximately 9.1 degrees, a swing weight of D4.1, a total club head weight (grip + shaft + head) of 317.6 grams, and a finished head weight of 204.6 grams.

[0110] The 1 degree lofted control club was lofted (via an adjustable hosel) to have a clubhead with a loft angle of approximately 8.1 degrees, a swing weight of D4.1, a total clubhead weight (grip + shaft + head) of 317.6 grams, and a finished head weight of 204.6 grams.

[0111] Additionally, various characteristic time measurements were recorded for the center and high-toe quadrants at various locations on the control club. The table below (Table 1) summarizes the values ​​recorded. The measurement location at the (0 in, 0 in) point location is defined at the geometric center (or origin) of the golf club head. Moving from right to left on the table adjusts the horizontal reference location, therefore moving it closer to the toe of the club head. Moving from bottom to top on the table adjusts the vertical reference location, therefore moving it towards the crown of the club head.

[0112] [Table 1]

[0113] For comparison purposes, the center-high tow characteristic time values ​​were also measured for the tested embodiment of Figure 7 and are shown in Table 2. Comparing Tables 1 and 2, it can be seen that at critical locations on the faceplate (i.e., the center-high tow quadrant), the characteristic time measurements before (Table 1) and after (Table 2) the spot weld decreased by an average of approximately 4% or 12 μs.

[0114] [Table 2]

[0115] Typically, a decrease in characteristic time results also results in a decrease in ball speed. However, this was not the case. Specifically, with reference to Figure 11, it can be seen that across center, toe, and heel impacts, ball speed for the tested club increased relative to the control club and the higher lofted control club. Furthermore, with reference to Figures 12 and 13, it can be seen that the tested club head launched approximately 8% lower with approximately 9% less spin.

[0116] It was concluded that this phenomenon was due to both impact velocity and localized face plate hardening. The characteristic time test is a low (or slow) impact test that measures the time a golf ball remains in contact with the face plate upon impact. Alternatively, ball velocity data is typically taken at high speed impacts with the golf ball. As such, the club heads described herein with HAZ (and more specifically, face plate response) vary according to low and high impact settings.

[0117] For example, at characteristic time measurement locations where the heat-affected zone is present, the heat-affected zone is stiffer than adjacent (non-HAZ) locations due to smaller grain boundaries. The heat-affected zone does not allow the face plate to flex as much, resulting in a reduced CT (at a particular location) due to the stiffer region. Thus, the golf ball does not stay in contact with the face plate as long upon impact. However, at high impacts (such as a full swing) when the overall system is stiffer, the heat-affected zone generates increased ball velocity, and therefore, energy transfer to the golf ball upon impact is not lost due to reduced face bending and / or curvature in certain regions as the face bends.

[0118] Substitution of one or more claimed elements constitutes a reconstruction, not a repair. Furthermore, benefits, other advantages, and solutions to problems have been described with respect to particular embodiments. However, the benefits, advantages, solutions to problems, and any elements that may give rise to or make more apparent any benefit, advantage, or solution should not be construed as a critical, essential, or essential feature or element of any or all of the claims.

[0119] Because the rules of golf are subject to change frequently (e.g., new rules may be adopted, or old rules may be eliminated or modified, by golf standards organizations and / or governing bodies such as the United States Golf Association (USGA), the Royal and American Golf Association (R&A), etc.), golf equipment related to the apparatus, methods, and articles of manufacture described herein may or may not conform to the rules of golf at any particular time. Accordingly, golf equipment related to the apparatus, methods, and articles of manufacture described herein may be advertised, marketed, and / or sold as conforming or non-conforming golf equipment. The apparatus, methods, and articles of manufacture described herein are not limited in this respect.

[0120] Furthermore, the embodiments and limitations disclosed herein are not available to the public under the doctrine of dedication if the embodiment and / or limitation (1) is not explicitly claimed in the claims and (2) is equivalent or potentially equivalent to elements and / or limitations expressly stated in the claims under the doctrine of equivalents.

[0121] Various features and advantages of the disclosure are set forth in the following claims.

[0122] Item 1. A face plate and a body, the body comprising a sole, a crown, a heel end, and a toe end, the sole being on the ground at address, the crown being opposite the sole, the heel end being opposite the toe end and perpendicular to the sole and the crown, the face plate having a geometric center that is equidistant from the crown and the sole and equidistant from the heel end and the toe end, the face plate defining a loft plane, the loft plane intersecting the ground and tangent to the geometric center, the face plate and the body, and a reference shape having a height and a width, the reference shape being measured from the geometric center to the 10. A golf club head comprising: a reference shape extending toward a crown and a toe, wherein the height of the reference shape is approximately 25% of an overall height of the face plate measured in the loft plane in a crown-sole direction and the width of the reference shape is approximately 25% of an overall width of the face plate measured perpendicular to the loft plane in a heel-to-toe direction; the reference shape further comprising a characteristic time threshold, wherein one or more locations within the reference shape include a characteristic time value greater than the characteristic time threshold; and a first heat-affected zone formed at or near the one or more locations, wherein each heat-affected zone location after formation includes a characteristic time value less than or equal to the characteristic time threshold.

[0123] Item 2. The golf club head according to Item 1, wherein the geometric center of the face plate further defines an origin for a coordinate system having an X' axis and a Y' axis, the X' axis extending through the geometric center of the face plate in a direction from the heel to the toe of the club head, and the Y' axis extending from the crown to the sole of the club head through the geometric center of the face plate in a direction perpendicular to the X' axis, forming four face plate quadrant regions including a center-high toe quadrant, and the reference shape is a rectilinear reference shape extending from the geometric center of the face plate and bounded only by the center-high toe quadrant.

[0124] Item 3. The golf club head according to Item 2, wherein the linear reference shape is angled at an angle of about 20 degrees to about 80 degrees with respect to the X' axis.

[0125] Item 4. The golf club head according to Item 3, wherein the linear reference shape is angled at an angle of about 45 degrees to about 50 degrees with respect to the X' axis.

[0126] Item 5. The golf club head of item 2, wherein at least the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are present along the linear reference shape, and the first, second, third, and fourth heat-affected zones have a microstructure that is different from the microstructure of a non-heat-affected faceplate region.

[0127] Item 6. The golf club head of item 5, wherein the microstructure of the first, second, third, and fourth heat-affected zones is a needle-like or finger-like structure with smaller grain boundaries than the microstructure of the non-heat-affected faceplate region.

[0128] Item 7. The golf club head of item 1, wherein the first heat-affected zone extends over no more than 16.5% of the exterior face plate surface area.

[0129] Item 8. The golf club head according to item 5, wherein the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are substantially collinear with one another.

[0130] Item 9. The golf club head according to item 8, wherein the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are not present at any position along the face plate-to-body transition region.

[0131] Item 10. A face plate and a body, the body comprising a sole, a crown, a heel end, and a toe end, the sole being on the ground at address, the crown being opposite the sole, the heel end being opposite the toe end and perpendicular to the sole and the crown, the face plate having a geometric center equidistant from the crown and the sole and equidistant from the heel end and the toe end, the face plate defining a loft plane, the loft plane intersecting the ground and tangent to the geometric center, the face plate and the body, and a reference shape having a height and a width, the reference shape being a distance from the geometric center to the crown and extending toward the toe end, wherein the height of the reference shape is about 5% to about 25% of an overall height of the face plate measured in the loft plane in a crown-sole direction and the width of the reference shape is about 5% to about 25% of an overall width of the face plate measured perpendicular to the loft plane in a heel-to-toe direction, the reference shape further comprising a characteristic time threshold, wherein one or more locations within the reference shape include a characteristic time value greater than the characteristic time threshold, and a first heat-affected zone is formed at or near the one or more locations, and each formed heat-affected zone location includes a characteristic time value less than or equal to the characteristic time threshold.

[0132] Item 11. The golf club head according to Item 10, wherein the geometric center of the face plate further defines an origin for a coordinate system having an X' axis and a Y' axis, the X' axis extending through the geometric center of the face plate in a direction from the heel to the toe of the club head, and the Y' axis extending from the crown to the sole of the club head through the geometric center of the face plate in a direction perpendicular to the X' axis, forming four face plate quadrant regions including a center-high toe quadrant, and the reference shape is a linear reference shape extending from the geometric center of the face plate and bounded only by the center-high toe quadrant.

[0133] Item 12. The golf club head according to Item 11, wherein the linear reference shape is angled at an angle of about 20 degrees to about 80 degrees with respect to the X' axis.

[0134] Item 13. The golf club head according to Item 12, wherein the linear reference shape is angled at an angle of about 45 degrees to about 50 degrees with respect to the X' axis.

[0135] Item 14. The golf club head of item 11, wherein at least the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are present along the linear reference shape, and the first, second, third, and fourth heat-affected zones have a microstructure that is different from the microstructure of a non-heat-affected faceplate region.

[0136] Item 15. The golf club head of item 14, wherein the microstructure of the heat-affected zone is a needle-like or finger-like structure forming smaller grain boundaries than the microstructure of the non-heat-affected faceplate region.

[0137] Item 16. The golf club head of item 10, wherein the first heat-affected zone spans no more than 16.5% of the exterior face plate surface area.

[0138] Item 17. The golf club head according to item 14, wherein the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are collinear with one another.

[0139] Item 18. The golf club head according to Item 17, wherein the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are not present at any position along the face plate-to-body transition region.

[0140] Item 19. The golf club head according to Item 11, wherein the golf club head is a driver-type club head.

[0141] Item 20. The golf club head according to Item 11, wherein the golf club head is a driver-type club head having a loft angle of less than 10 degrees.

Claims

1. a face plate and a body, the body including a sole, a crown, a heel end, and a toe end; The sole is on the ground at address, the crown is opposite the sole; the heel end is opposite the toe end and perpendicular to the sole and the crown; the face plate has a geometric center that is equidistant from the crown and the sole and equidistant from the heel end and the toe end; the face plate defining a loft plane, the loft plane intersecting the ground surface and tangent to the geometric center; the faceplate further comprising an area defined by a reference shape having a height and a width; the reference shape extends from the geometric center toward the crown and the toe end; the height of the reference shape is approximately 25% of an overall height of the face plate measured in the loft plane in a crown-sole direction; the width of the reference shape is about 25% of an overall width of the face plate measured perpendicular to the loft plane in a heel-to-toe direction; the region defined by the reference shape further comprises, at one or more locations, a characteristic time value greater than a predetermined characteristic time threshold; the faceplate further comprising first heat affected zones at or near the one or more locations, each heat affected zone including a characteristic time value less than or equal to the predetermined characteristic time threshold; the first heat affected zone is formed by a spot weld having a diameter of less than about 0.75 inches, the first heat affected zone having a diameter of less than about 50% of the diameter of the spot weld; The golf club head, wherein the physical grain structure of the first heat affected zone is a dendritic microstructure.

2. the geometric center of the faceplate further defines an origin for a coordinate system having an X' axis and a Y' axis; the X' axis extends through the geometric center of the face plate in a direction from the heel end to the toe end of the golf club head, and the Y' axis extends through the geometric center of the face plate in a direction perpendicular to the X' axis from the crown to the sole of the golf club head, forming four face plate quadrant regions including a center-high toe quadrant; The golf club head of claim 1 , wherein the reference shape is a rectilinear reference shape extending from the geometric center of the face plate and bounded only by the center-high toe quadrant.

3. 3. The golf club head of claim 2, wherein the linear reference shape is angled at an angle of about 20 degrees to about 80 degrees relative to the X' axis.

4. 4. The golf club head of claim 3, wherein the linear reference shape is angled at an angle of about 45 degrees to about 50 degrees relative to the X' axis.

5. 3. The golf club head of claim 2, wherein at least the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are located along the linear reference shape, and the first, second, third, and fourth heat-affected zones have a microstructure that is different from a microstructure of a non-heat-affected faceplate region.

6. 6. The golf club head of claim 5, wherein the microstructure of the first, second, third, and fourth heat-affected zones is a needle-like or finger-like structure with smaller grain boundaries than the microstructure of the non-heat-affected faceplate region.

7. The golf club head of claim 1 , wherein the first heat affected zone extends over no more than 16.5% of the exterior face plate surface area.

8. The golf club head of claim 5 , wherein the first heat affected zone, the second heat affected zone, the third heat affected zone, and the fourth heat affected zone are substantially collinear with one another.

9. 9. The golf club head of claim 8, wherein the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are not present at any location along the face plate-to-body transition region.

10. a face plate and a body, the body including a sole, a crown, a heel end, and a toe end; The sole is on the ground at address, the crown is opposite the sole; the heel end is opposite the toe end and perpendicular to the sole and the crown; the face plate has a geometric center that is equidistant from the crown and the sole and equidistant from the heel end and the toe end; the face plate defining a loft plane, the loft plane intersecting the ground surface and tangent to the geometric center; the faceplate comprises an area defined by a reference shape having a height and a width; the reference shape extends from the geometric center toward the crown and the toe end; the height of the reference shape is between about 5% and about 50% of an overall height of the face plate measured in the loft plane in a crown-sole direction; the width of the reference shape is about 5% to about 50% of an overall width of the face plate measured perpendicular to the loft plane in a heel-to-toe direction; the region defined by the reference shape further comprises, at one or more locations, a characteristic time value greater than a predetermined characteristic time threshold; a first heat affected zone at or near said one or more locations, each heat affected zone including a characteristic time value less than or equal to said predetermined characteristic time threshold; the first heat affected zone comprises a spot weld having a diameter of less than about 0.75 inches, the first heat affected zone having a diameter of less than about 50% of the diameter of the spot weld; The golf club head, wherein the physical grain structure of the first heat affected zone is a dendritic microstructure.

11. the geometric center of the faceplate further defines an origin for a coordinate system having an X' axis and a Y' axis; the X' axis extends through the geometric center of the face plate in a direction from the heel end to the toe end of the golf club head, and the Y' axis extends through the geometric center of the face plate in a direction perpendicular to the X' axis from the crown to the sole of the golf club head, forming four face plate quadrant regions including a center-high toe quadrant; The golf club head of claim 10 , wherein the reference shape is a rectilinear reference shape extending from the geometric center of the face plate and bounded only by the center-high toe quadrant.

12. The golf club head of claim 11, wherein the linear reference shape is angled at an angle of between about 20 degrees and about 80 degrees relative to the X' axis.

13. The golf club head of claim 12, wherein the linear reference shape is angled at an angle of about 45 degrees to about 50 degrees relative to the X' axis.

14. 12. The golf club head of claim 11, wherein at least the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are located along the linear reference shape, and the first, second, third, and fourth heat-affected zones have a microstructure that is different from a microstructure of a non-heat-affected faceplate region.

15. 15. The golf club head of claim 14, wherein the microstructure of the heat affected zone is needle-like or finger-like, forming smaller grain boundaries than the microstructure of the non-heat affected faceplate region.

16. The golf club head of claim 10 , wherein the first heat affected zone extends over no more than 16.5% of the exterior face plate surface area.

17. The golf club head of claim 14 , wherein the first heat affected zone, the second heat affected zone, the third heat affected zone, and the fourth heat affected zone are collinear with one another.

18. 18. The golf club head of claim 17, wherein the first heat-affected zone, the second heat-affected zone, the third heat-affected zone, and the fourth heat-affected zone are not present anywhere along the face plate-to-body transition region.

19. 11. The golf club head of claim 10, wherein the spot weld has a diameter of less than about 0.70 inches and the first heat affected zone has a diameter of less than about 45% of the diameter of the spot weld.

20. 11. The golf club head of claim 10, wherein the spot weld has a diameter of less than about 0.65 inches and the first heat affected zone has a diameter of less than about 40% of the diameter of the spot weld.

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