Protrusion forming method, molding manufacturing method, molding manufacturing apparatus, molding, and die

Abstract

To provide a protrusion forming method that allows alignment or partial changes in size, pitch, and height and the like of protrusions.SOLUTION: Protrusions are formed using a die 11, for a metallic molding comprising a substrate and protrusions vertically raised from the substrate. The die 11 comprises an opening which is open to a surface; and a formation part 21 having formation holes communicating with the opening and constituted of internal spaces existing inside the molding. One surface 102 of a metallic material 101 is abutted and placed on the opening of the die 11. A rotary tool 41 is moved while pressing the rotating rotary tool 41 against the other surface 103 different from the one surface 102 of the metallic material 101, whereby protrusions are formed inside the formation holes according to hardening of a plastic fluid material entered into the internal spaces. After forming the protrusions, the protrusions are removed from the formation holes.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a method for forming a protrusion, a method for manufacturing a molded body, an apparatus for manufacturing a molded body, a molded body, and a molding die. [Background technology]

[0002] Heat sinks are often used in cooling parts for inverters, converters, etc. used in eco-friendly vehicles. Some of these heat sinks are manufactured by a forging method, in which pin fins are formed by pouring metal material that has been plastically deformed by forging into fin-forming holes in a die. However, a problem with this forging method is that the height of the pin fins is not uniform. To address the issues with these forging methods, Patent Document 1 describes a backpressure forging method in which backpressure applying pins are set in the fin forming holes and backpressure is applied by the backpressure applying pins to make the pin fins uniform in height. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5941037 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the technology of Patent Document 1, pressure is applied to the metal material placed on multiple fin forming holes as a whole, making it difficult to make changes such as partially changing the size of the pin fins, partially changing the pitch of the pin fins, or partially changing the height of the pin fins. From this perspective, the present invention aims to provide a method for forming protrusions, a method for manufacturing a molded body, an apparatus for manufacturing a molded body, and a molding die, which allow the size, pitch, height, etc. of the protrusions to be uniform or partially changed. [Means for solving the problem]

[0005] In order to solve such problems, the first invention is a method for forming a protrusion in a metal molded body having a base and a protrusion erected from the base, using a molding die, the molding die having a forming part having a forming hole consisting of an opening that opens into the surface of the molding die and an internal space existing inside the molding die that communicates with the opening, the method comprising: a positioning step of positioning a metal material with one side abutting on the opening of the molding die; a forming step of moving a rotating tool while pressing the rotating tool against the other side of the metal material that is different from the one side, thereby forming the protrusion in the forming hole by hardening the plastic flow material that has flowed into the internal space; and a removal step of removing the protrusion from the forming hole after the protrusion is formed.

[0006] It is preferable that the formation hole extends straight from the opening toward the inside of the mold, and the height of the formation hole is greater than the diameter of the opening.

[0007] It is preferable that the cross-sectional shape of the formation hole on the side behind the opening is larger than the cross-sectional shape on the opening side.

[0008] It is preferable.

[0009] It is preferable that the rotating tool has a base and a conical tip portion continuous with the base, the tip portion having a spiral groove on its surface, and the tip portion is brought into contact with the metal material during the forming process.

[0010] It is preferable that the tip portion has a truncated cone shape having a tapered side portion centered on the rotation axis of the rotating tool and a tip surface portion at its tip that is perpendicular to the rotation axis of the rotating tool.

[0011] It is preferable that the spiral groove has a step portion consisting of step side surfaces extending in a direction approximately parallel to the rotation axis of the rotating tool and a step bottom surface facing a direction approximately perpendicular to the rotation axis, and that the step portion rotates in a spiral manner so that the step bottom surface of the step portion is adjacent to the step side surface of the step portion located on the outer periphery of the tip portion and the step side surface of the step portion is adjacent to the step bottom surface of the step portion located on the inner periphery of the tip portion, and that the step bottom surface is provided with a recess recessed in the direction of the rotation axis.

[0012] The depth of the spiral groove is preferably 0.1 to 1.0 mm.

[0013] The taper angle of the tip is preferably 100 to 175°.

[0014] It is preferable that the protrusions are pin fins, and the molded body is a heat sink having the pin fins as the protrusions.

[0015] A second aspect of the present invention is characterized in that the protrusions are formed by the method for forming protrusions described above, and the molded body is obtained.

[0016] The molded article is preferably a heat sink having pin fins as the protrusions.

[0017] A third invention is a manufacturing apparatus for a metal molded body having a base and a protrusion erected from the base, in which the protrusion is formed using a molding die to obtain the molded body, the manufacturing apparatus comprising: a molding die having a forming part having a forming hole consisting of an opening opening on the surface of the molding die and an internal space existing inside the molding die and connected to the opening; and a rotating tool that rotates and presses against a surface different from the one surface of a metal material arranged with one surface abutting on the opening of the molding die, and by moving the rotating tool while pressing it against the metal material, the protrusion is formed in the forming hole by hardening of the plastic flow material that has flowed into the internal space.

[0018] A fourth invention is a metal molded body comprising a base and a protrusion extending upright from the base, wherein the base and the protrusion are integrally formed from the same metal material, the protrusion consists only of a plasticized region of the metal material, and is formed by gradually deforming from the base, and further extends straight from the base.

[0019] A fifth invention is a molding die for forming the protrusion, which comprises a base and a protrusion erected from the base, the molding die having a forming hole consisting of an opening opening on a surface and an internal space existing inside the forming hole and communicating with the opening, the metal material is placed with one side in contact with the opening, and a rotating tool is pressed against the other side of the metal material different from the one side while the rotating tool is moved, so that the protrusion is formed in the forming hole by hardening of the plastic flow material that has flowed into the internal space, and then a knock pin is pressed against the one side of the metal material from the forming hole side to demold the protrusion from within the forming hole. Effect of the Invention

[0020] According to the present invention, the size, pitch, height, etc. of the protrusions can be uniform or partially changed. [Brief description of the drawings]

[0021] [Figure 1] FIG. 2 is a perspective view of a molded article according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective view of a molding die according to an embodiment of the present invention, as viewed from above. [Diagram 3] FIG. 2 is a perspective view of a molding die according to an embodiment of the present invention, viewed from below. [Figure 4] 3 is a cross-sectional view taken along line AA in FIG. 2. [Diagram 5] FIG. 5 is an enlarged view of part B in FIG. [Figure 6]FIG. 2 is a front view of a rotary tool according to an embodiment of the present invention. [Figure 7] FIG. 4 is a bottom view of the tip of a rotary tool according to an embodiment of the present invention. [Figure 8] FIG. 2 is an enlarged vertical cross-sectional view of a spiral groove of the rotary tool according to the embodiment of the present invention. [Figure 9] 5A to 5C are vertical cross-sectional views illustrating a placement step in the method for forming a protrusion according to the embodiment of the present invention. [Figure 10] 5A to 5C are vertical cross-sectional views illustrating a forming step in the method for forming a protrusion according to the embodiment of the present invention. [Figure 11] 5A to 5C are plan views illustrating a forming step in the method for forming a protrusion according to the embodiment of the present invention. [Figure 12] 5A to 5C are enlarged vertical cross-sectional views illustrating a forming step in the method for forming a protrusion according to the embodiment of the present invention. [Figure 13] 5 is a vertical cross-sectional view illustrating a separation step (before separation) in the method for forming a protrusion according to the embodiment of the present invention. FIG. [Figure 14] 5 is a vertical cross-sectional view illustrating a detachment step (after detachment) in the method for forming a protrusion according to the embodiment of the present invention. FIG. [Figure 15] 10A and 10B are plan views showing examples of other shapes (rectangular shapes) of protrusions in a molded article according to an embodiment of the present invention. [Figure 16] 10A to 10C are plan views showing examples of other shapes (rectangular shapes with different orientations) of protrusions in a molded article according to an embodiment of the present invention. [Figure 17] 10A and 10B are plan views showing examples of other shapes (triangular shapes) of protrusions in a molded article according to an embodiment of the present invention. [Figure 18] 3A to 3C are plan views showing examples of the shape (rectangular shape) of an opening in a casting mold according to an embodiment of the present invention. [Figure 19] 3A to 3C are plan views showing examples of the shape (water drop shape) of an opening in a casting mold according to an embodiment of the present invention. [Figure 20] 3A to 3C are plan views showing examples of the shape (flat shape) of an opening in a casting mold according to an embodiment of the present invention. [Figure 21]FIG. 2 is a front view of a tip portion of a shoulderless type rotating tool for friction stir welding used as Comparative Example 1. [Figure 22] 13 is a photograph, substituted for a drawing, showing a front view of a tip portion of a rotating tool for friction stir welding used in Comparative Example 2. [Figure 23] 10A is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph in lieu of a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph in lieu of a drawing that is a plan view of the protrusion after molding. [Figure 24] 10A is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. [Diagram 25] 4A and 4B are diagrams for explaining Example 4 of the present invention, in which (a) is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. [Figure 26] 5A and 5B are diagrams for explaining Example 5 of the present invention, in which (a) is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. [Figure 27] 6A and 6B are diagrams for explaining Example 6 of the present invention, in which (a) is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. [Figure 28] 7A and 7B are diagrams for explaining Example 7 of the present invention, in which (a) is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. [Figure 29]8A and 8B are diagrams for explaining Example 8 of the present invention, in which (a) is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. [Diagram 30] 9A and 9B are diagrams for explaining Example 9 of the present invention, in which (a) is a plan view showing the movement trajectory and depression amount of the rotary tool, (b) is a photograph as a substitute for a drawing that is a plan view of the metal material after the rotary tool has been moved, and (c) is a photograph as a substitute for a drawing that is a plan view of the protrusion after molding. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The embodiments of the present invention will be described with reference to the drawings as appropriate. The present invention is not limited to the following embodiments. In addition, some or all of the components in the embodiments can be combined as appropriate. Furthermore, the drawings are intended to conceptually explain the present invention, and the dimensions and ratios of each component shown may differ from the actual ones.

[0023] [1. Molded body] 1 is a perspective view of a molded body according to an embodiment of the present invention. The molded body 1 is, for example, a metal member having a plate-shaped base body 2 and one or more protrusions 3 standing up from one surface of the base body 2. In this example, the base body 2 has a rectangular shape in a plan view. In this example, the molded body 1 is a heat sink having pin fins, which are the protrusions 3, standing up from the base body 2, and is used as a cooling part for cooling inverters, converters, and the like.

[0024] The base 2 and the protrusion 3 are integrally formed from the same metal material, such as aluminum, aluminum alloy, copper, copper alloy, etc., in this example, aluminum alloy. The base 2 can be formed from a wrought material containing the above-mentioned metal material. The protrusion 3 consists only of a plasticized region of the metal, is formed by gradually deforming from the base 2, and further extends straight from the base 2.

[0025] In this embodiment, the shape of each protrusion 3 is a columnar (rod-like) shape having a radial cross-sectional shape such as a circle, a triangle, or a rectangle. The cross-sectional shape of the protrusion 3 may be a semicircle, a partial circle, an ellipse, a polygon having pentagons or more, a star, a teardrop (waterdrop), a shape in which two partial arcs are combined (flat shape), a small wave shape, an indefinite shape, or a combination of these shapes. Furthermore, the shape of the protrusion 3 may be a plate shape (wall-like, mountain range-like). The protrusion 3 may be solid (shaft-like) or hollow (tubular, frame-like). The shapes of the multiple protrusions 3 may be the same or different from each other. The sizes (height, diameter) of the multiple protrusions 3 may be the same or different from each other.

[0026] In this embodiment, the multiple protrusions 3 are regularly arranged in a hexagonal lattice shape with intervals between each other. The arrangement of the protrusions 3 can be changed as appropriate depending on the properties required for the molded body 1. The arrangement of the protrusions 3 may be, for example, a regular arrangement in a hexagonal lattice shape, a square lattice shape, a rectangular lattice shape, or a parallelepiped lattice shape, or may be a random irregular arrangement. The intervals at which the multiple protrusions 3 are arranged may be constant or may be varied.

[0027] If the protrusions 3 are circular, the orientation of the protrusions 3 does not matter, but if the protrusions 3 are other than circular, the orientation in which the protrusions 3 are arranged can be changed as appropriate depending on the properties required for the molded body 1. The protrusions 3 may be arranged so that they are aligned in the same orientation, may be arranged in alternating orientations, or may be arranged in random, irregular orientations.

[0028] [2.Mold] A molding manufacturing apparatus is used to manufacture the above-mentioned molded body 1. This molding manufacturing apparatus includes a mold and a rotary tool. In the following, first, the configuration of the mold will be described, and then the configuration of the rotary tool will be described.

[0029] FIG. 2 is a perspective view of a molding die 11 according to an embodiment of the present invention as viewed from above, FIG. 3 is a perspective view of the same as viewed from below, and FIG. 4 is a cross-sectional view taken along line AA in FIG. 2. The molding die 11 is a metal mold for molding and manufacturing the molded body 1. The molding die 11 is made of tool steel. The molding die 11 includes a lower die 12 having an approximately rectangular parallelepiped appearance and a plate-like upper die 13 placed on the lower die 12 and thinner than the lower die 12. The lower die 12 and the upper die 13 have the same shape (rectangular) when viewed from above. The molding die 11 includes an auxiliary plate 15 that can be freely inserted and removed from the bottom of the lower die 12, and four knock pins 16 (see FIG. 14) in this example that can be freely inserted and removed by vertically penetrating the upper die 13, the lower die 12, and the auxiliary plate 15.

[0030] A forming section 21 for forming the protrusion 3 is provided in the center of the upper mold 13 and the lower mold 12 in a top view. In the forming section 21, a plurality of forming holes 22 are formed that penetrate vertically from the upper mold 13 to the lower mold 12. Directly below the forming section 21 of the lower mold 12, an auxiliary plate storage section 23 is formed as a space that opens from the lower surface of the lower mold 12. The auxiliary plate storage section 23 is a space that can store, for example, a rectangular parallelepiped-shaped auxiliary plate 15 from the lower surface side of the lower mold 12. When the auxiliary plate 14 is stored in the auxiliary plate storage section 23, the upper surface of the auxiliary plate 15 reaches the lower surface of the forming section 21 on the lower mold 12 side. At this time, the side surface of the auxiliary plate 15 in the auxiliary plate storage section 23 reaches the outside of the outer edge of the region of the forming section 21 in a top view. In other words, the size of the auxiliary plate 15 is sufficiently larger than the forming section 21, and the lower parts of all the forming holes 22 are blocked by the auxiliary plate 15. The auxiliary plate 15 is positioned so that it does not come into contact with the extending inflow metal 121 (see FIGS. 12 and 13) when the protruding portion 3 is formed, or comes into slight contact with the inflow metal 121.

[0031] In this example, holes are provided on the outside of the four corners of forming portion 21, penetrating upper die 13, lower die 12, and auxiliary plate 15. These holes are upper die knock pin hole 25 in upper die 13, lower die knock pin hole 26 in lower die 12, and auxiliary plate knock pin hole 27 in auxiliary plate 14. When upper die 13, lower die 12, and auxiliary plate 15 are combined as shown in Figures 2 to 4, knock pin 16 (see Figure 14) can be inserted from the upper die 13 side so as to pierce upper die knock pin hole 25, lower die knock pin hole 26, and auxiliary plate knock pin hole 27.

[0032] As shown in Fig. 14, the knock pin 16 is, for example, a cylindrical shaft-like member, and has a flange portion 28 that protrudes radially outward only at the upper end. The upper portion of the upper knock pin hole 25 of the upper die 13 has a stepped portion 29, and the stepped portion 29 can engage with the flange portion 28. Therefore, when the knock pin 16 is inserted through the upper knock pin hole 25, the lower knock pin hole 26, and the auxiliary plate knock pin hole 27 (see Fig. 4), the stepped portion 29 engages with the flange portion 28. The knock pin 16 is set to a length that does not protrude downward from the lower die 12. The upper end surface of the knock pin 16 is set so as not to protrude from the upper surface of the upper die 13.

[0033] FIG. 5 is an enlarged vertical cross-sectional view of the forming hole 22 provided in the forming section 21 (enlarged view of part B in FIG. 4). The forming hole 22 has an opening 31 that opens to the surface of the upper mold 13 of the mold 11, and an internal space 32 that communicates with the opening 31 and exists inside (at the back) of the mold 11 (upper mold 13, lower mold 12). The internal space 32 is composed of an upper hole 33 formed in the upper mold 13 and a lower hole 34 formed in the lower mold 12. The upper hole 33 penetrates the upper mold 13, and the lower hole 34 penetrates the lower mold 12. Thus, in this embodiment, the forming hole 22 is a hole that penetrates the mold 11 from top to bottom, but it does not necessarily have to be a through hole. However, a through hole is preferable because it is easier for gas, air, etc. to escape.

[0034] The forming hole 22 extends straight from the opening 31 toward the inside of the mold 11. The forming hole 22 has a vertically elongated shape with its height H1 being larger than the diameter Φ1 of the opening 31. The forming hole 22 is shaped like a cylinder, a prism, or the like. The cross-sectional shapes of the opening 31 and the upper hole 33 are the same in the length direction. The forming hole 22 may be a tapered cone shape or may have a step in the middle, so long as it extends straight. If the forming hole 22 is bent, curved, or spiral-shaped, it is not appropriate because it will not be possible to perform the demolding described later. Here, "straight" means "without bending." In other words, the forming hole 22 does not have to extend vertically from the top surface (upper mold 13) of the mold 11. Therefore, the forming hole 22 may extend obliquely from the opening 31 toward the inside of the mold 11 as long as it is straight. However, when forming hole 22 extends obliquely into forming die 11, forming hole 22 also extends obliquely into forming die 11, and forming hole 22 and knock pin 16 are formed in parallel.

[0035] The cross-sectional shape of the formation hole 22 on the side behind the opening 31 is larger than the cross-sectional shape on the opening 31 side. Specifically, the cross-sectional shape of the lower hole 34 formed in the lower mold 12 is larger than the cross-sectional shape of the upper hole 33 formed in the upper mold 13.

[0036] In the formation hole 22, the cross-sectional shape of the lower hole 34 on the back side of the opening 31 is the same as or larger than the circumscribing circle of the cross-sectional shapes of the opening 31 and the upper hole 33. For example, when the protrusion 3 is triangular prism-shaped, the cross-sectional shapes of the opening 31 and the upper hole 33 of the formation hole 22 are triangular, and the cross-sectional shape of the lower hole 34 on the back side is the same as or larger than the circumscribing circle of the triangle of the opening 31 and the upper hole 33. In other words, as long as the cross-sectional shape of the lower hole 34 on the back side is the same as or larger than the circumscribing circle of the cross-sectional shapes of the opening 31 and the upper hole 33, the cross-sectional shapes of the opening 31 and the lower hole 34 may be different.

[0037] As described above, a plurality of forming holes 22 are formed in the forming portion 21, and the plurality of forming holes 22 extend in the same direction at the same angle. The shape, size, arrangement and orientation of the formation holes 22 can be appropriately set in accordance with the shape, size, arrangement and orientation of the protrusions 3 to be provided on the molded body 1 to be manufactured.

[0038] [3. Rotation tool] Fig. 6 is a front view of a rotary tool according to an embodiment of the present invention. Fig. 7 is a bottom view of the tip of the rotary tool. The rotary tool 41 is a tool that softens a metal material by pressing it against the metal material while rotating. The rotary tool 41 is made of tool steel. The rotary tool 41 has a columnar or frustum-shaped base 42 and a conical tip 43 that is continuous with the base 42. A spiral groove 47 is provided on the surface of the tip 43. The rotary tool 41 is rotated in the circumferential direction as described below, and the tip 43 is brought into contact with the metal material.

[0039] The base 42 is, for example, cylindrical, and a flange portion 44 is formed on the base end side thereof, protruding outward toward the outer periphery, and a base end portion 91, for example, cylindrical and having a smaller diameter than the base 42, is provided on the further base end side of the flange portion 44. The rotating tool 41 is attached to a device such as a machining center via the base end portion 91 when in use.

[0040] The tip portion 43 has a tapered side portion 45 on its side centered on the rotation axis C of the rotation tool 41, and is a truncated cone shape having a tip surface portion 46 at its tip, which is provided continuously from the side portion 45 toward the tip side and has a surface shape perpendicular to the rotation axis C of the rotation tool 41. The surface shape of the tip surface portion 46 may be a flat surface or a curved surface (convex portion, concave portion). In the tip portion 43 of the rotation tool 41, the tip surface portion 46 is provided continuously from the side portion 45 in which the spiral groove 47 is provided, and no pin-shaped protrusion is provided at the tip of the tip portion 43.

[0041] The taper angle θ1 of the tip portion 43 is 100 to 175°. The taper angle θ1 is more preferably 115 to 165°, further preferably 130 to 155°, and particularly preferably 140 to 145°.

[0042] The spiral groove 47 is provided so as to spirally wrap around from the center side of the rotary tool 41 and expand in the outer circumferential direction. The number of turns of the spiral groove 47 is preferably one or more turns, more preferably two or more turns, even more preferably three or more turns, and particularly preferably five or more turns. The spiral groove 47 may be formed by a single spiral groove wrapping around, or may be formed by two or more spiral grooves wrapping around in parallel to each other.

[0043] 8 is an enlarged vertical cross-sectional view of the spiral groove 47. The spiral groove 47 has a step portion 53 consisting of a step side surface 51 extending in a direction substantially parallel to the rotation axis C (FIG. 5) of the rotation tool 41 and a step bottom surface 52 facing in a direction substantially perpendicular to the rotation axis C. When the rotation tool 41 is viewed in cross section on a plane passing through the rotation axis, the step portion 53 spirally goes around the side surface portion 45, and the step side surface 51 and the step bottom surface 52 of the step portion 53 at different turns are adjacent to each other and are repeatedly formed. Specifically, the step portion 53 spirally goes around, and thus a first step portion 53a consisting of a first step side surface 51a and a first step bottom surface 52a, a second step portion 53b consisting of a second step side surface 51b and a second step bottom surface 52b, and a third step portion 53c consisting of a third step side surface 51c and a third step bottom surface 52c are formed in this order from the outer periphery side. In this case, the second step bottom surface 52b of the second step portion 53b is adjacent to the first step side surface 51a of the first step portion 53a located on the outer periphery side of the tip portion 43. Also, the second step side surface 51b of the second step portion 53b is adjacent to the third step bottom surface 52c of the third step portion 53c located on the inner periphery side of the tip portion 43. In this manner, the step portions 53 are repeatedly formed adjacent to each other while spirally going around the side portion 45, and no tapered surface formed by the taper angle of the tapered tip portion 43 exists between adjacent step portions 53.

[0044] The step bottom surface 52 is provided with a recess 54 recessed in the direction of the rotation axis C. The step bottom surface 52 and the recess 54 form a step bottom 55. That is, the step portion 53 spirally goes around the side surface portion 45, with the second step bottom 55b of the second step portion 53b adjacent to the first step side surface 51a of the first step portion 53a located on the outer periphery, and the second step side surface 51b of the second step portion 53b adjacent to the third step bottom 55c of the third step portion 53c located on the inner periphery, and is repeatedly formed. The step side surface 51 located on the outer periphery of the step bottom surface 52 and the recess 54 provided in the step bottom surface 52 form a protruding portion 56 protruding in the direction of the rotation axis C toward the tip side of the tool. In this way, the shape of the spiral groove 47 is neither step-shaped (step-shaped) nor screw-shaped.

[0045] The cross-sectional shape of the recess 54 provided in the spiral groove 47 is an arc shape in this embodiment, but it may be an ellipse, a rectangle, a triangle, etc. From the viewpoint of suppressing accumulation of metal material in the recess 54, it is preferable that the cross-sectional shape of the recess 54 is an arc shape.

[0046] The recess 54 may be provided on the entire step bottom surface 52, or may be provided on a part of the step bottom surface 52 by being provided at a distance from the inner peripheral end or the outer peripheral end of the step bottom surface 52. The recess 54 is provided at a distance from the inner peripheral end of the step bottom surface 52 to form an inner peripheral step bottom surface 57. The recess 54 is provided at a distance from the outer peripheral end of the step bottom surface 52 to form an outer peripheral step bottom surface 58. The recess 54 is provided at the outer peripheral end of the step bottom surface 52, so that the protruding portion 56 has a pointed shape toward the tip side of the tool. When the recess 54 is provided at the outer peripheral end of the step bottom surface 52, the protruding portion 56 is easily worn due to its sharpness. For this reason, it is preferable that the recess 54 is provided at a distance from the outer peripheral end of the step bottom surface 52 to form the outer peripheral step bottom surface 58. In this embodiment, in the step bottom surface 52. On both sides of where the recess 54 is provided, an inner peripheral step bottom surface 57 and an outer peripheral step bottom surface 58 remain as flat portions where no recess 54 is formed.

[0047] The recess 54 is preferably lower (shallower) than the height of the step bottom surface 52 located on the outer periphery side of the step bottom surface 52 on which the recess 54 is provided. The recess is also preferably lower (shallower) than the height of the protruding portion 56 formed in the step portion 53 located on the outer periphery side of the step bottom surface 52 on which the recess 54 is provided. In the step bottom portion 55 on which the recess 54 is provided, the depth of the recess 54 is preferably lower (smaller) than the height of the step side surface 51. This makes it possible to prevent the metal material from accumulating in the recess 54, and makes it easier for the tip portion 43 to uniformly push out the metal material.

[0048] The depth H2 of the spiral groove 47 is 0.2 mm to 1.5 mm. The depth H2 means the length between the most recessed portion of the recess 54 provided in the step bottom surface 52 and the most protruding portion of the protruding portion 56 of the step side surface 51 adjacent to the step bottom surface 52 on the inner peripheral side in the direction of the rotation axis C of the rotating tool 41. The depth H2 is more preferably 0.3 to 1.3 mm, and further preferably 0.5 to 1.2 mm. The depth H2 of the spiral groove 47 is preferably 5 to 30% of the height of the tip portion 43, more preferably 8 to 27%, and further preferably 11 to 25%.

[0049] The pitch (spacing) P1 of the spiral groove 47 is 0.5 to 2.5 mm. The pitch P1 means the average spacing of the spiral groove 47 formed in a plane perpendicular to the rotation axis C of the rotating tool 41, spirally circling from the center side of the rotation axis C and spreading outward. The pitch P1 is more preferably 0.7 to 2.0 mm, and even more preferably 1.0 to 1.8 mm. The pitch of the spiral groove 47 is preferably 2 to 15% of the diameter of the tip portion 43, more preferably 4 to 10%, and even more preferably 5 to 9%.

[0050] [4. Method of forming protrusions] Next, a method for forming the protrusions for producing the green body 1 using the molding die 11 and the rotary tool 41 (a method for producing the green body) will be described step by step.

[0051] (Placement process) FIG. 9 is a vertical cross-sectional view for explaining the arrangement step in the method for forming the protrusion of this embodiment. First, the forming die 11 is assembled in the state shown in FIG. 2 to FIG. 4. That is, the upper die 13 is aligned and placed on the lower die 12, the auxiliary plate 15 is inserted into the auxiliary plate storage portion 23, and the four knock pins 16 are inserted as described above so as to penetrate them vertically. Then, for example, a plate-shaped metal material 101 is arranged with one surface 102 thereof abutting against the upper surface 14 so as to cover the entire area (FIG. 4) of the forming portion 21 of the upper surface 14 of the upper die 13 and the range of all the knock pins 16. Then, in this state, each part is fixed with a predetermined jig (not shown in the drawing) so as not to be displaced. As the metal material 101, aluminum, aluminum alloy, copper, copper alloy, etc. can be used as described above, but in this embodiment, an aluminum alloy wrought material is used.

[0052] (Formation process) After the placement step, the formation step is carried out. Fig. 10 is a vertical cross-sectional view for explaining the formation step in the method for forming a protrusion of this embodiment. While pressing a rotary tool 41 (black arrow) rotating around a rotation axis C against the other surface 103 (upper surface) different from the one surface 102 of the metal material 101, the rotary tool 41 is moved (white arrow) on the metal material 101 in a direction parallel to the other surface 103 of the metal material 101. Note that, in this embodiment, the one surface 102 and the other surface 103 are in a positional relationship in which they face each other, but the positional relationship of these surfaces may be changed as long as the plastic flow described below can be appropriately generated in the metal material 101.

[0053] FIG. 11 is a plan view for explaining the forming process in the method for forming the protrusion of this embodiment. The starting point 111 of the movement of the rotary tool 41 on the metal material 101 is the center of the region where the forming portion 21 (FIGS. 2 and 4) of the upper mold 13 is formed. The moving trajectory 112 of the rotary tool 41 on the metal material 101 starting from the moving starting point 111 is a spiral starting from the center in this example. The plasticized region formed by the movement of the rotary tool 41 is gradually moved outward while overlapping at a predetermined pitch (about several millimeters). That is, the moving trajectory 112 is a curve that moves around the center so as not to cross. In this embodiment, the moving trajectory 112 is a circular spiral curve that moves around the center while gradually increasing the distance from the center, but it may be an oval or elliptical spiral curve. This moving trajectory 112 is merely an example, and moving trajectories of various shapes can be implemented. For example, the movement trajectory 112 may be set to be linear, or may be set as a straight line that moves around the center while changing the movement direction. Also, the start point of the movement trajectory 112 may be set on the outside, and the end point of the movement may be set in the center of the area where the forming portion 21 of the mold 13 is formed. The end point of this movement trajectory 112 is, for example, a position after the rotary tool 41 has passed directly above or near at least all of the forming holes 22 (FIGS. 2, 4, and 5). It is preferable that the friction forging is performed continuously from the start point to the end point of the movement trajectory 112. Here, when the movement trajectory 112 of the rotary tool 41 is a counterclockwise trajectory, the rotary tool 41 is rotated right, and when the movement trajectory 112 of the rotary tool 41 is a clockwise trajectory, the rotary tool 41 is rotated left. In the example of FIG. 11, the latter is the case.

[0054] 12 is an enlarged vertical cross-sectional view illustrating the forming process in the method for forming the protrusion of this embodiment. The tip 43 of the rotating rotary tool 41 is pressed against the metal material 101, so that the metal material 101 is rubbed by the rotary tool 41 and undergoes plastic flow and softens. In the forming process, the pushing amount of the rotary tool 41 is set so that the tip 43 comes into contact with the other surface 103 of the metal material 101. At this time, it is preferable to set the pushing amount so that the entire tip 43 is not inserted deeper than the other surface 103 of the metal material 101, and the boundary position between the tip 43 and the base 42 is at the same height as the other surface 103 of the metal material 101, or the boundary position between the tip 43 and the base 42 is shallower than the other surface 103 of the metal material 101, and the base 42 side of the tip 43 is exposed. The softened metal material (plastic flow material) 101 flows into the forming hole 22, and this inflow metal 121 extends to the rear side of the internal space 32 with its cross-sectional shape being formed by the opening 31 and the upper hole 33. At this time, the cross-sectional shape of the lower hole 34 is larger than the cross-sectional shapes of the opening 31 and the upper hole 33, and the diameter of the lower hole 34 is partially the same as or larger than the diameter Φ1 (FIG. 5) of the opening 31, so that a gap is generated between the outer peripheral surface of the inflow metal 121 extending to the rear side of the internal space 32 and the inner peripheral surface of the lower hole 34.

[0055] In this way, after the metal material 101 is softened and a part of it is flowed into the forming hole 22, when a predetermined time has passed, the softened metal material 101 cools and solidifies. Then, the flowed-in metal 121 becomes the protruding portion 3, and the metal material 101 remaining on the forming die 11 becomes the base 2, and the above-mentioned molded body 1 having the protruding portion 3 protruding from the base 2 can be integrally formed.

[0056] Various conditions for pressing and moving the rotary tool 41 against the metal material 101 can be set according to the purpose, etc. Such conditions include the rotation speed of the rotary tool 41, the moving speed of the rotary tool 41, the pitch between adjacent plasticized regions, the indentation amount of the rotary tool 41 against the metal material 101, the indentation load, etc. In particular, by controlling the indentation amount of the rotary tool 41, it is possible to make the heights of the multiple protrusions 3 uniform or different.

[0057] When forming the protrusion 3, it is preferable that the extended inflow metal 121 is formed to a height that does not contact the auxiliary plate 14. In other words, it is preferable that the inflow metal 121 is formed to a height that does not reach the entire length of the lower hole 34. By preventing the inflow metal 121 from contacting the auxiliary plate 15, it is possible to prevent deformation such as bending or crushing of the inflow metal 121 and the protrusion 3 caused by contact between the inflow metal 121 and the auxiliary plate 15. However, from the viewpoint of aligning the heights of the multiple protrusions 3, the inflow metal 121 may be slightly in contact with the auxiliary plate 15.

[0058] (Removal process) After the forming step, the removing step is performed. Figures 13 and 14 are vertical cross-sectional views for explaining the removing step in the method for forming the protrusion of this embodiment. As shown in Figure 13, first, the auxiliary plate 14 is removed from the auxiliary plate storage section 23, the molding die 11 from which the auxiliary plate 15 has been removed is turned upside down, and the support parts 71 protruding from both sides of the molding die 11 are supported on the pedestal parts 72 to support the molding die 11 in an upside-down state. Then, an auxiliary jig 73 having the same dimensions as the auxiliary plate 15 and no hole such as the auxiliary plate knock pin hole 27 is inserted into the auxiliary plate storage section 23 from which the tip side of the knock pin 16 is exposed due to the removal of the auxiliary plate 15. In this case, the auxiliary jig 73 may be hit from above with a hammer or the like as necessary.

[0059] 14, by inserting auxiliary jig 73 into auxiliary plate storage section 23, knock pin 16 is pushed in by auxiliary jig 73. This causes the tip of knock pin 16 to be pressed against one surface 102 of metal material 101 from the forming hole 22 side, peeling metal material 101 from molding die 11 and demolding protrusion 3. In this way, completed molded body 1 can be demolded from molding die 11.

[0060] The molded body 1 can be manufactured in the above manner. In the example of FIG. 1, the shape of the protrusion 3 of the molded body 1 is exemplified as a circular cross section. FIGS. 15 to 17 are all plan views showing examples of other shapes of the protrusion. FIG. 15 is an example in which the shape of the protrusion 3 is rectangular, and a plurality of protrusions 3 are arranged in a hexagonal lattice pattern, and the direction of the rectangle is parallel to one of the three non-intersecting sides forming the hexagonal lattice. FIG. 16 is an example in which the shape of the protrusion 3 is the same rectangular shape as in FIG. 15, and the protrusions 3 are arranged in a hexagonal lattice pattern, but the direction of the rectangle is different from that in FIG. 15, and the direction of the rectangle is not parallel to any of the three non-intersecting sides forming the hexagonal lattice, but is inclined. FIG. 17 is an example in which the shape of the protrusion 3 is triangular, and a plurality of protrusions 3 are arranged in a hexagonal lattice pattern, and the direction of the triangle is uniform on one of the three non-intersecting sides forming the hexagonal lattice, but the direction of the triangle alternates for each parallel side.

[0061] These shapes can be controlled by making the shape of opening 31 of molding die 11 desired. Figures 18 to 20 are plan views showing examples of the shapes of the openings. Figure 18 shows an example of a rectangular opening 31. Figure 19 shows an example of an approximately water-drop shaped opening 31. Figure 20 shows an example of an approximately elliptical (flat) opening 31 with sharpened ends. In this way, by changing the shape of opening 31, protrusion 3 having a desired cross-sectional shape can be formed.

[0062] [5. Effects] According to the method for forming the protrusion (the method for manufacturing the molded body) of this embodiment described above, the following advantageous effects can be achieved. In the forging method of Patent Document 1, the entire metal material to be processed is pressurized. In contrast, in this embodiment, the metal material 101 can be partially pressurized by friction forging using a rotating rotary tool 41. In addition, according to this embodiment, the size, pitch, or height of the protrusion 3 can be partially changed by controlling conditions such as the rotation speed of the rotary tool 41, the movement speed of the rotary tool 41, the pitch between adjacent movement trajectories 112, and the amount of pressing of the rotary tool 41 into the metal material 101, and by designing the mold 11. In addition, the number, shape, size, arrangement, etc. of the forming holes 22 provided in the mold 11 can be changed. Therefore, according to this embodiment, a molded body 1 in which the heights of the protrusions 3 are uniform can be manufactured according to these friction forging conditions and the mold 11. In addition, according to this embodiment, a molded body 1 in which the shape, size, pitch, or height of the protrusions 3 in a desired portion is partially different from other portions can be manufactured according to the friction forging conditions and the mold 11.

[0063] The forging method of Patent Document 1 requires a large forging machine and a complex forging die, whereas this embodiment can form the protrusion 3 using a simple forming die 11 having a forming hole 22 and a normal machining center. Therefore, this embodiment can manufacture the molded body 1 having the protrusion 3 at low manufacturing cost.

[0064] Forming hole 22 extends straight from opening 31 toward the inside of forming die 11. Furthermore, forming hole 22 has a height H1 greater than the diameter Φ1 of opening 31. Therefore, the plastic flow material generated from metal material 101 can smoothly flow into forming hole 22, and protrusion 3 can be formed straight to match the shape of opening 31. This allows the operation of removing protrusion 3 from inside forming hole 22 to be performed smoothly.

[0065] Here, for example, if the shape of the internal space of the formation hole 22 is a columnar shape with a constant diameter or a tapered shape, etc., there is a problem that it is difficult to remove the protrusion 3 from the mold because the protrusion 3 comes into contact with the inner wall surface at the back of the formation hole 22. In addition, if the formation hole has a tapered shape, there is a problem that the pressure on the protrusion 3 increases when the protrusion 3 is formed, making it difficult to form the protrusion 3. In contrast, in the present embodiment, the cross-sectional shape of the forming hole 22 on the side behind the opening 31 is larger than the cross-sectional shape on the opening 31 side. Specifically, the cross-sectional shape of the lower hole 34 formed in the lower die 12 is larger than the cross-sectional shape of the upper hole 33 formed in the upper die 13. This creates a space between the lower hole 34 and the protruding portion 3, making it easier to remove the protruding portion 3 after molding. Also, since the plastic flow material does not come into contact with the lower hole 34 even during the molding stage, molding accuracy can be improved.

[0066] The cross-sectional shape of the lower hole 34 of the forming hole 22, which is located on the inner side of the opening 31, is the same as the circumscribed circle shape of the cross-sectional shape of the opening 31 or is larger than the circumscribed circle shape of the cross-sectional shape of the opening 31. This makes it easy to remove the protrusion 3 after molding.

[0067] The molding die 11 is configured with a lower die 12 and an upper die 13 as separate bodies, with an opening 31 and an upper hole 33 provided in the upper die 13, and a lower hole 34 provided in the lower die 12. As a result, for example, if it is desired to change the cross-sectional shape of the protrusion 3, it is only necessary to replace the upper die 13 with one having the opening 31 and upper hole 33 of the desired shape, while leaving the lower die 12 as is. In other words, with the molding die 11, protrusions 3 having various cross-sectional shapes can be easily molded.

[0068] Also, for example, the lower hole 34 of the lower die 12 can be made to have a round cross section by end milling, and the upper hole 33 of the upper die 13 can be made to have a triangular cross section by wire cutting. In this way, the lower die 12 and the upper die 13 are configured as separate bodies, so that the opening 31 and the upper hole 33, and the lower hole 34 can be made to have different shapes by using different processing methods, compared to when the lower die 12 and the upper die 13 are configured as an integral body. This increases the degree of freedom in the shape of the forming die 11.

[0069] Moreover, in order to prevent the inflow metal 121 from adhering to the upper hole 33, it is necessary to prevent the thickness of the upper die 13 from being excessively thick. On the other hand, if the upper die 13 is thin, the upper die 13 may bend when it receives a load from the rotating tool 41 in the forming process, causing the protruding portion 3 to be deformed or the protruding portion 3 to become unable to be removed from the upper die 13. The lower die 12 and the upper die 13 are configured as separate bodies, and while the upper die 13 receives the load from the rotating tool 41, the lower die 12 supports the load from the opposite side to the rotating tool 41, thereby making it possible to suppress deformation of the upper die 13.

[0070] Furthermore, the upper die 13, which receives the load from the rotary tool 41, is relatively more susceptible to wear and damage than the lower die 12. Since the lower die 12 and the upper die 13 are configured as separate bodies, even if the upper die 13 is worn or damaged, only the upper die 13 can be replaced, thereby reducing the repair costs of the forming die 11.

[0071] A plurality of forming holes 22 are formed in the forming portion 21, and these plurality of forming holes 22 extend in the same direction at the same angle. Therefore, even if a plurality of forming holes 22 are present, the protruding portion 3 can be easily punched out from the forming holes 22.

[0072] Here, for example, if the tip 43 of the rotary tool 41 has a stepped shape in a spiral shape or a screw shape, there is a risk that the plastic material will not be sufficiently entrained and the pressing force for flowing into the forming hole 22 will also be small. In contrast, the rotary tool 41 of this embodiment has a base 42 having a columnar or cone-like shape and a tip 43 having a conical shape continuous with the base 42. A helical groove 47 is provided on the surface of the tip 43. Therefore, by bringing the tip 43 provided with the helical groove 47 into contact with the metal material 101, the plastic material can be easily entrained through the helical groove 47 and flowed into the forming hole 22.

[0073] For example, if the tip of the rotary tool has a tapered shape, the amount of metal material pushed from the tip of the rotary tool in the direction of the rotation axis C may decrease. In contrast, in this embodiment, the tip portion 43 has a truncated cone shape having a tapered side portion 45 centered on the rotation axis C of the rotary tool 41 on the side and a tip surface portion 46 perpendicular to the rotation axis C of the rotary tool 41 at the tip. That is, the plastic flow material guided by the side portion 45 can be pushed in the direction of the forming hole 22 by the tip surface portion 46 of the rotary tool 41, so that the protrusion 3 can be stably formed. In addition, since the rotary tool 41 of this embodiment has a truncated cone shape, a punch hole is less likely to remain when the rotary tool 41 is removed compared to when the tip of the rotary tool has a tapered shape. This improves the design freedom of the molded body 1. In addition, by omitting post-processing such as cutting to remove the punch hole, productivity can be improved.

[0074] The spiral groove 47 has a step portion 53 consisting of a step side surface 51 extending in a direction substantially parallel to the rotation axis C of the rotary tool 41 and a step bottom surface 52 facing a direction substantially perpendicular to the rotation axis C. This step portion 53 spirally goes around the side surface portion 45, and the step bottom surface 52b of the step portion 53b is adjacent to the step side surface 51a of the step portion 53a located on the outer periphery side of the tip portion 43, and the step side surface 51b of the step portion 53b is adjacent to the step bottom surface 52c of the step portion 53c located on the inner periphery side of the tip portion 43, and is repeatedly formed. The step bottom surface 52 is provided with a recess 54 recessed in the direction of the rotation axis C. Such a shape of the spiral groove 47 can improve the performance of raking in the metal material 101 and guiding it to the tip side of the rotary tool 41.

[0075] The depth H2 of the spiral groove 47 is 0.1 to 1.0 mm. This allows the plastic material to be guided to the tip side of the tip portion 43 via the spiral groove 47, making it easier to form the protrusion 3. The taper angle θ1 of the tip portion 43 is 100 to 175°. This increases the contact area between the tip portion 43 and the metal material 101, making it easier to guide the plastic material to the tip side of the tip portion 43 and form the protrusion 3.

[0076] In the forming process, when the movement locus 112 of the rotating tool 41 is a counterclockwise locus, the rotating tool 41 is rotated clockwise, and when the movement locus 112 of the rotating tool 41 is a clockwise locus, the rotating tool 41 is rotated counterclockwise. As a result, as the rotating tool 41 rotates (spins), the metal material 101 in the portion where plastic flow is not caused can be drawn toward the inner peripheral side of the movement locus 112 of the rotating tool 41.

[0077] In the forming process, it is possible to make the heights of the plurality of protrusions 3 uniform by controlling the amount of depression of the rotary tool 41. The reason for this will be described in the examples.

[0078] [6.Other] Although the embodiment of the present invention has been described above, appropriate design changes are possible without departing from the spirit of the present invention.

[0079] In the above-mentioned embodiment, the case where the molded body 1 is a heat sink has been described as an example. The molded body 1 and the manufacturing method for the molded body 1 can be used as an object including a base 2 and a protruding portion 3 and a manufacturing method thereof. For example, the molded body 1 can be a support table using the protruding portion 3 as a foothold, and the molded body 1 can be a housing (case) in which the protruding portion 3 is formed into a wall shape.

[0080] In the above embodiment, the molding die 11 is described as being configured such that the lower die 12 and the upper die 13 are separate bodies. The molding die 11 may be configured such that the lower die 12 and the upper die 13 are integral with each other.

[0081] In the above-described embodiment, the rotating tool 41 is described by way of example with the cone-shaped tip portion 43 on the base portion 42. The rotating tool 41 is not limited as long as it can cause the plastic material to flow into the forming hole 22. For example, the rotating tool 41 may be cylindrical with a flat or concave surface on the bottom surface portion located at the tip of the base portion 42. However, in this case, it is preferable that the bottom surface portion of the base portion 42 has a spiral groove from the viewpoint of facilitating the flow of the plastic material into the forming hole 22 by raking it in. EXAMPLES

[0082] The following describes the contents of various experimental data, focusing on examples of the present invention. <Experimental Data 1> A comparison was made between Example 1 and Comparative Examples 1 and 2, which are as follows. In the molding die 11 used in each of the following Examples and Comparative Examples, when forming a protrusion 3 having a circular cross section, the diameter of the opening 31 is 2.0 mm, and the diameter of the lower hole 34 is 2.2 mm.

[0083] Example 1 The rotary tool 41 described with reference to Figs. 6 to 8 was prepared in two types of rotary tools 41 with different taper angles, and the above-mentioned molded body 1 was manufactured. In both of the two types of rotary tools 41, the diameter size of the base 42 was 20 mm, the diameter size of the tip surface portion 46 was 3 mm, and the pitch of the spiral groove 47 was 1.5 mm. In the first rotary tool 41, the taper angle θ1 of the tip portion 43 was 120°, the height of the tip portion 43 was 5.8 mm, and the depth H2 of the spiral groove 47 was 0.87 mm. In the second rotary tool 41, the taper angle θ1 of the tip portion 43 was 135°, the depth H2 of the spiral groove 47 was 0.62 mm, and the height of the tip portion 43 was 4.1 mm. In addition, the metal material 101 used was a plate material having a thickness of 6 mm made of aluminum alloy A1050 in all the following data. The driving conditions of the rotary tool 41 were a rotation speed of 3000 rpm, a moving speed of 500 mm / min, and a pressing amount of 3.6 mm into the metal material 101. The starting point 111 of the movement of the rotary tool 41 was set to the center of the area where the forming portion 21 was formed. The moving path 112 of the rotary tool 41 was a spiral shape with a pitch of 3 mm that started from the center and spread outward while rotating. The pressing amount is the distance from the other surface 103 of the metal material 101 to the tip surface portion 46.

[0084] As a result, although specific illustration is omitted, when the first rotating tool 41 with the taper angle θ1 of 120° was used, a compact 1 with an average height of the protrusions 3 of about 6 mm could be manufactured. When the second rotating tool 41 with a taper angle θ1 of 135° was used, a compact 1 with an average height of the protrusions 3 of about 8 mm could be manufactured.

[0085] Comparative Example 1 FIG. 21 is a front view of a tip portion of a shoulderless type rotation tool for friction stir welding used as Comparative Example 1. This rotation tool 201 is used in place of the rotation tool 41, and includes a cylindrical base 202 and a conical tip 203 continuous with the base 202. The tip 203 has a tapered side surface 204 on the side and a truncated cone shape having a tip surface 205 at the tip. In this Comparative Example 1, the tip 203 has a taper angle θ2 of 105° and 120°. The rotation tool 201 is significantly different from the rotation tool 41 in that, while the rotation tool 41 forms the spiral groove 47 as described above, the rotation tool 201 forms a step-like step (not shown in the drawing) on ​​the side surface 204, which is composed of a step side surface extending in a direction approximately parallel to the rotation axis of the rotation tool 201 and a step bottom surface facing in a direction approximately perpendicular to the rotation axis, instead of a spiral groove. Two types of rotating tools 201 were prepared, each having a base 202 with a diameter of 14 mm, a tip surface 205 with a diameter of 1.5 mm, a step pitch of 0.75 mm, and a tip 203 with a taper angle θ2 of 105° and 120°.

[0086] The driving conditions of the rotary tool 201 were a rotation speed of 3000 rpm, a moving speed of 500 mm / min, and a pressing amount into the metal material 101 of 3.8 mm. The starting point 111 of the movement of the rotary tool 201 was set to the center of the region where the forming portion 21 was formed. The moving trajectory of the rotary tool 201 was a spiral shape with a pitch of 3 mm, starting from the center and spreading outward while rotating. Under these conditions, the rotary tool 201 was used instead of the rotary tool 41, and the mold 11 was used to manufacture the molded body 1 in the same process as in the above embodiment. As a result, when the rotating tool 201 with a taper angle θ2 of 105° was used, the average height of the protrusions 3 of the produced compact 1 was about 1 mm.

[0087] When the rotating tool 201 with a taper angle θ2 of 120° was used, the average height of the protrusions 3 of the produced compact 1 was about 2 mm.

[0088] Comparative Example 2 FIG. 22 is a drawing substitute photograph showing a front view of the tip of the rotation tool for friction stir welding used in Comparative Example 2. This rotation tool 211 is a funnel-type tool. The tip 212 of the rotation tool 211 includes a tapered base end 213 and a tapered tip end 214 continuous with the base end 213. The taper angle of the base end 213 is 150°, and the taper angle of the tip end 214 is 60°. The taper angle of the base end 213 is larger than the taper angle of the tip end 214. A step-like step is formed in the base end 213, and a screw-like groove is formed in the tip end 214. The diameter size of the base of the rotation tool 211, that is, the diameter of the root part of the base end 213 is 20 mm, the diameter of the root part of the tip end 214 is 6 mm, and the diameter size of the tip surface part provided at the tip of the tip end 214 is 2 mm.

[0089] The driving conditions of the rotating tool 211 were a rotation speed of 3000 rpm, a moving speed of 500 mm / min, and a pressing amount into the metal material 101 of 3.8 mm. The starting point 111 of the movement of the rotating tool 211 was set to the center of the region where the forming portion 21 was formed. The moving trajectory of the rotating tool 211 was a spiral shape with a pitch of 3 mm, starting from the center and spreading outward while rotating. Under these conditions, the rotating tool 211 was used instead of the rotating tool 41, and the above-mentioned forming die 11 was used to manufacture the molded body 1 in the same process as in the embodiment. As a result, the average height of the protrusions 3 of the produced molded body 1 was about 0 to 0.5 mm, and almost no protrusions 3 could be formed.

[0090] (evaluation) Comparing the results of Example 1 with those of Comparative Examples 1 and 2, it is found that in Example 1, a protrusion 3 of sufficient height could be formed, but in Comparative Examples 1 and 2, a protrusion 3 of sufficient height could not be formed, or almost no protrusion 3 could be formed. Therefore, Example 1 using the rotary tool 41 was able to obtain better results than Comparative Examples 1 and 2.

[0091] <Experimental Data 2> An experiment was carried out to manufacture a compact 1 by changing the amount of pressing of the rotary tool 41 in various ways during the movement trajectory 112 of the rotary tool 41 and setting various other driving conditions of the rotary tool 41. In the following Examples 2 to 9, a second rotary tool 41 with a taper angle θ1 of 135° was used.

[0092] 23 to 30 show the contents of individual examples. In each figure, (a) shows a spiral movement locus 112 starting from the center of the rotary tool 41, and each number attached thereto indicates the amount of depression of the rotary tool 41 into the metal material 101. For example, in FIG. 23(a), the amount of depression is initially set to 2.6 mm, set to 2.8 mm after about half a turn, and set to 3.2 mm after about one turn. It is further set to 3.0 mm, 3.4 mm, and 3.6 mm every about half a turn. The movement start point 111 of the rotary tool 41 is set to the center of the area where the forming portion 21 is formed. In addition, the movement locus 112 of the rotary tool 41 is a spiral shape with a pitch of 3 mm that starts from the center and spreads outward while rotating.

[0093] In addition, in each figure, (b) is a photograph substituting a drawing that is a plan view of the metal material 101 after the rotating tool 41 has been moved, and (c) is a photograph substituting a drawing that is a plan view of the protrusion after it has been formed by driving the rotating tool 41. In each of the following examples, experiments were carried out under various conditions with the goal of making the height of each protrusion 3 uniform at 10 mm.

[0094] Example 2 23(a), (b), and (c) are diagrams showing the contents of the experiment in Example 2. In Example 2, the driving conditions of the rotating tool 41 are a rotation speed of 3000 rpm, a moving speed of 1000 mm / min, and a pressing amount into the metal material 101 of 2.6 to 3.6 mm as shown in FIG. As a result, the height of the protrusion 3 was about 1 to 3.5 mm shorter overall than the target height of 10 mm. There was variation in the height of the protrusion 3. In Fig. 23(c), the height of the protrusion 3 was greater in the area indicated by the dashed line than in other areas.

[0095] Example 3 24(a), (b), and (c) are diagrams showing the contents of the experiment in Example 3. In Example 3, the driving conditions of the rotary tool 41 are a rotation speed of 3000 rpm, a moving speed of 1000 mm / min, and a pressing amount into the metal material 101 of 3.2 to 3.8 mm as shown in FIG. 24(a). As is clear from comparing FIG. 24(a) with FIG. 23(a), in Example 3, the pressing amount of the rotary tool 41 into the metal material 101 is made larger than that in Example 2.

[0096] As a result, the height of the formed protrusions 3 was greater than in Example 2, but was still about 1 to 2 mm shorter than the target height of 10 mm. There was still variation in the height of the protrusions 3. In Figure 24(c), the height of the protrusions 3 was greater in the area indicated by the dashed line than in other areas.

[0097] Example 4 25(a), (b), and (c) are diagrams showing the contents of the experiment in Example 4. In Example 4, the driving conditions of the rotary tool 41 are a rotation speed of 3000 rpm, a moving speed of 750 mm / min, and a pressing amount into the metal material 101 of 3.4 to 4.0 mm as shown in FIG. 25(a). As is clear from comparing FIG. 25(a) with FIG. 24(a), in Example 4, the pressing amount of the rotary tool 41 into the metal material 101 is made larger than that in Example 3.

[0098] As a result, by increasing the amount of pressing of the rotary tool 41 into the metal material 101, the height of the protrusions 3 became larger than that of Example 3. The target height of 10 mm for the protrusions 3 was achieved in the central portion of the group of protrusions 3, but the height of the protrusions 3 in the outer periphery was small and the target could not be achieved.

[0099] Example 5 26(a), (b), and (c) are diagrams showing the contents of the experiment of Example 5. In Example 5, the driving conditions of the rotary tool 41 are a rotation speed of 3000 rpm, a moving speed of 500 mm / min, and a pressing amount into the metal material 101 as shown in FIG. 26(a), which are the same as those of Example 4. In Example 5, the moving speed of the rotary tool 41 is made slower than those of Examples 2 to 4, with the intention of increasing the amount of heat input from the rotary tool 41 to the metal material 101.

[0100] As a result, it was possible to increase the height of the protrusions 3 arranged along the outer periphery, which was not high enough in Example 4. In other words, the target height of the protrusions 3, 10 mm, was almost achieved.

[0101] Example 6 27(a), (b), and (c) are diagrams showing the contents of the experiment of Example 6. In Example 6, the driving conditions of the rotating tool 41 are as shown in FIG. 27(a), that is, the rotation speed is 3000 rpm, the moving speed is 750 mm / min, and the pressing amount into the metal material 101 is the same as in Example 5. In each of the above examples, the protrusion 3 having a circular cross section is formed, but in this Example 6, the protrusion 3 having a triangular cross section with a smaller cross section area is formed. As a result, the height of the protrusion 3 could be increased by reducing the cross-sectional area of ​​the protrusion 3 to be formed, and the height of the protrusion 3 almost achieved the target height of 10 mm. There was also little variation in the height of the protrusion 3.

[0102] Example 7 28(a), (b), and (c) are diagrams showing the contents of the experiment of Example 7. In Example 7, the driving conditions of the rotating tool 41 are as shown in FIG. 28(a), that is, the rotation speed is 3000 rpm, the moving speed is 750 mm / min, and the pressing amount into the metal material 101 is the same as in Example 5. In the examples up to Example 4, the protruding portion 3 having a circular cross section was formed, but in this example 7, the protruding portion 3 having a rectangular cross section with a smaller cross section area was formed.

[0103] As a result, the height of the protrusion 3 could be increased by reducing the cross-sectional area of ​​the protrusion 3 to be formed, and the height of the protrusion 3 almost achieved the target height of 10 mm. There was also little variation in the height of the protrusion 3.

[0104] Example 8 Figures 29(a), (b), and (c) are diagrams showing the contents of the experiment of Example 8. In Example 8, the driving conditions of the rotary tool 41 were a rotation speed of 3000 rpm, a moving speed of 1250 mm / min, and a pressing amount into the metal material 101 as shown in Figure 29(a), which are the same as those of Example 5. In this Example 8, a protrusion 3 having a triangular cross section was formed similarly to that of Example 6. The moving speed of the rotary tool 41 was set faster than any of the above-mentioned examples.

[0105] As a result, the height of each of the protrusions 3 located on the outer periphery was not sufficiently high among the multiple protruding protrusions 3. This is presumably because the moving speed of the rotary tool 41 was too fast, resulting in insufficient thermal diffusion from the rotary tool 41 to the metal material 101.

[0106] Example 9 30(a), (b), and (c) are diagrams showing the contents of the experiment of Example 9. In Example 9, the driving conditions of the rotary tool 41 were a rotation speed of 3000 rpm, a moving speed of 1000 mm / min, and a pressing amount into the metal material 101 as shown in FIG. 29(a), which are the same as those of Example 5. In this Example 9, a protrusion 3 having a triangular cross section was formed similarly to that of Example 6. The moving speed of the rotary tool 41 was set slower than that of Example 8.

[0107] As a result, the height of each of the protrusions 3 located on the outer periphery of the array of the multiple protruding protrusions 3 was not sufficiently high. However, since the moving speed of the rotating tool 41 was slower than in Example 8, this was an improvement over Example 8.

[0108] (evaluation) In the experimental data 2, a target was set to manufacture a molded body 1 having a uniform height of 10 mm for the protrusions 3, and multiple experiments were carried out under various conditions. In terms of best meeting the target, the most suitable results were obtained in Examples 6 and 7. The results of the experimental data 2 revealed that the height of the multiple protrusions 3 protruding from the molded body 1 can be changed depending on the location by changing various conditions. Therefore, it was also shown that by changing various conditions, a molded body 1 in which the height of the protrusions 3 varies depending on the location can be manufactured. For example, according to the present invention, the height of the protrusions 3 can be changed between the center and the outer periphery of the row of the protrusions 3. Furthermore, according to the present invention, the size, pitch, etc. of the protrusions 3 can also be partially changed by designing the molding die 11. [Explanation of symbols]

[0109] 1 Molded body (heat sink) 2 Base 3. Pin fins 11 Mold (production equipment for molded bodies) 16 Knock pin 21 Formation part 22 Formation hole 31 Opening 32 Interior Space 41 Rotating tool (molding body manufacturing equipment) 42 Base 43 Tip 45 Side part 46 Tip surface section 47 Spiral groove 51 Step side 52 Bottom of step 53 Step 54 Recess 101 Metal materials 102 One Side 103 The other side C Rotational Axis

Claims

1. 1. A method for forming a protrusion in a metal molded body including a base and a protrusion extending from the base, the method comprising the steps of: the mold comprises a forming part having a forming hole including an opening that opens to a surface of the mold and an internal space that is in communication with the opening and exists inside the mold; a positioning step of positioning a metal material with one surface of the metal material in contact with the opening of the mold; a forming process in which a rotating tool is moved while pressing the rotating tool against another surface of the metallic material different from the one surface, thereby forming the protrusion in the forming hole by hardening the plastic flow material that has flowed into the internal space; and a detachment step of detaching the protrusion from the formation hole after the protrusion is formed. A method for forming a protrusion, comprising:

2. the forming hole extends straight from the opening toward the inside of the mold, The height of the formation hole is greater than the diameter of the opening. The method for forming a protrusion according to claim 1 .

3. The formation hole has a cross-sectional shape on a side deeper than the opening that is larger than a cross-sectional shape on the side closer to the opening. The method for forming a protrusion according to claim 1 .

4. The forming hole has a cross-sectional shape on a side deeper than the opening that is the same as a circumscribing circle shape of the cross-sectional shape of the opening or a shape larger than the circumscribing circle shape of the cross-sectional shape of the opening. The method for forming a protrusion according to claim 1 .

5. The rotary tool includes a base and a cone-shaped tip connected to the base, A spiral groove is provided on the surface of the tip portion, In the forming step, the tip portion is brought into contact with the metal material. The method for forming a protrusion according to claim 1 .

6. The tip portion has a side surface having a tapered shape centered on the rotation axis of the rotation tool, and has a truncated cone shape having a tip surface portion at a tip thereof perpendicular to the rotation axis of the rotation tool. The method for forming a protrusion according to claim 5 .

7. the spiral groove has a step portion including a step side surface extending in a direction substantially parallel to a rotation axis of the rotation tool and a step bottom surface facing in a direction substantially perpendicular to the rotation axis, the step portion is formed in a spiral manner such that the step bottom surface of the step portion is adjacent to the step side surface of the step portion located on the outer periphery side of the tip portion, and the step side surface of the step portion is adjacent to the step bottom surface of the step portion located on the inner periphery side of the tip portion, The step bottom surface is provided with a recess recessed in the direction of the rotation axis. The method for forming a protrusion according to claim 5 .

8. The depth of the spiral groove is 0.1 to 1.0 mm. The method for forming a protrusion according to claim 5 .

9. The taper angle of the tip is 100 to 175°. The method for forming a protrusion according to claim 5 .

10. The protrusion is a pin fin, The molded body is a heat sink having the pin fins as the protrusions. The method for forming a protrusion according to claim 1 .

11. The method for forming a protrusion according to claim 1 is used to form the protrusion, thereby obtaining the molded body. The method for producing a molded body comprising the steps of:

12. The molded body is a heat sink having pin fins as the protrusions. A method for producing the molded article according to claim 11.

13. 1. An apparatus for manufacturing a molded body, the apparatus comprising: a base body; and a protrusion portion extending upright from the base body, the apparatus being configured to obtain the molded body by forming the protrusion portion using a molding die, the apparatus comprising: The manufacturing apparatus includes: a mold including a forming part having a forming hole including an opening that opens to a surface of the mold and an internal space that is connected to the opening and exists inside the mold; a rotary tool that rotates and is pressed against a surface of a metal material that is different from the one surface of the metal material that is placed in contact with the opening of the mold; by moving the rotary tool while pressing the rotary tool against the metal material, the plastic flow material that has flowed into the internal space is hardened to form the protrusion in the forming hole. A molding manufacturing apparatus comprising:

14. A metal molded body including a base and a protruding portion extending from the base, the base and the protrusion are integrally formed from the same metal material, The protrusion is made of only a plasticized region of the metal material, is formed by gradually deforming from the base, and extends straight from the base. A molded article characterized by:

15. A mold for forming a metal molded body having a base and a protruding portion extending from the base, comprising: A forming part having a forming hole including an opening that opens to a surface and an internal space that is connected to the opening and exists inside the forming part, a metal material is placed with one surface of the metal material in contact with the opening, and a rotating tool is moved while pressing the other surface of the metal material different from the one surface of the metal material to form the protrusion in the forming hole by hardening the plastic flow material that has flowed into the internal space, and then a knock pin is pressed against the one surface of the metal material from the forming hole side to punch out the protrusion from within the forming hole; A molding die characterized by:

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