Cast-in product

Abstract

To improve bonding strength between a cast part and a member to be cast-in.SOLUTION: A cast-in product according to the present disclosure includes a cast part and a member to be cast-in, which are integrated by casting, wherein the cast-in product further includes a plurality of inclined holes each recessed from a contact surface of the member to be cast-in with the cast part and extending obliquely with respect to the contact surface. The member to be cast-in includes a plurality of protrusions each extending along at least a part of a periphery of each of the plurality of inclined holes. The plurality of inclined holes include: a plurality of first inclined holes disposed on one side of a boundary set in the cast-in product; and a plurality of second inclined holes disposed on the other side of the boundary. The plurality of first inclined holes are inclined in the same direction with each other, and the plurality of second inclined holes are inclined in a direction opposite to that of the plurality of first inclined holes.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an insert casting including a casting portion and an insert member that are integrated by insert casting. [Background technology]

[0002] Conventionally, cast iron components for insert casting, which are integrated with cast parts by insert casting, have been known to have an insert surface with a maximum surface roughness height Ry of 65 to 260 μm and a mean spacing Sm of irregularities of 0.6 to 1.5 mm (see, for example, Patent Document 1). This cast iron component for insert casting is manufactured using a suspension containing, as a coating material, 20 to 45 mass % of silica sand with an average particle size of 0.05 to 0.5 mm, 10 to 30 mass % of silica flour with an average particle size of 0.1 mm or less, 2 to 10 mass % of binder, and 30 to 60 mass % of water, and is used for cylinder blocks of vehicle engines and brake drum inserts. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-170755 Summary of the Invention [Problem to be solved by the invention]

[0004] However, even if the surface roughness of the inserted part that is integrated with the cast part by the insert casting is set within the range described above, it may not be possible to ensure sufficient bonding strength between the cast part and the inserted part.

[0005] Therefore, a primary object of the present disclosure is to improve the bonding strength between a cast portion and a cast-inserted member. [Means for solving the problem]

[0006] The insert casting product of the present disclosure is an insert casting product that includes a cast portion and an insert member that are integrated by insert casting, and includes a plurality of inclined holes that are recessed from the contact surface of the insert member with the cast portion and extend at an angle relative to the contact surface.

[0007] In the insert-cast product of the present disclosure, a plurality of inclined holes are formed in the contact surface between the insert and the cast portion of the insert member, each recessed from the contact surface and extending at an angle relative to the contact surface. As a result, during the production of the insert-cast product, a portion of the molten metal flows into the inclined holes of the insert member and solidifies and shrinks within each inclined hole. The metal in each inclined hole is then tightly adhered to the contact surface area of ​​the inner circumferential surface of each inclined hole due to stresses generated and remaining in response to solidification and shrinkage. As a result, the insert-cast product of the present disclosure can improve the bonding strength between the cast portion and the insert member.

[0008] In addition, the manufacturing method of the present disclosure is a manufacturing method of an insert cast product that includes a cast part and an insert member that are integrated by insert casting, in which a plurality of inclined holes are formed on the contact surface of the insert member with the cast part, each of which is recessed from the contact surface and extends at an angle relative to the contact surface, and after the insert member is placed in a mold, molten metal is poured into the mold and solidified.

[0009] This method also makes it possible to improve the bonding strength between the cast portion and the inserted member in an insert casting product. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing an insert casting according to the present disclosure; [Figure 2] FIG. 2 is a plan view showing an insert member included in the insert casting product of the present disclosure. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. [Figure 4] FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. [Figure 5]10 is a cross-sectional view showing another insert member included in the insert casting product of the present disclosure. [Figure 6] FIG. 10 is a schematic diagram showing another insert casting according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] Next, embodiments of the present disclosure will be described with reference to the drawings.

[0012] FIG. 1 is a schematic diagram showing an insert cast part 1 of the present disclosure. The insert cast part 1 shown in the figure forms a vehicle body structure (monocoque structure) and includes a cast part 2 and an insert member 3. The cast part 2 is formed by casting an aluminum alloy, for example, and is, for example, a torque box, a suspension tower, or an integrated torque box and suspension tower. The insert member 3 is, for example, a side member formed by extrusion molding an aluminum alloy different from the aluminum alloy forming the cast part 2. In the insert cast part 1, the insert member 3 is integrated with the cast part 2 so that both ends protrude from the cast part 2, as shown in FIG. 1.

[0013] FIG. 2 is a plan view showing the contact surface 3s of the insert member 3 with the casting portion 2. As shown in FIG. 2, a large number (plurality) of first inclined holes 31 and a large number (plurality) of second inclined holes 32 are formed in the contact surface 3s of the insert member 3 prior to placement in the mold. The large number of first inclined holes 31 are disposed on one side (left side in FIG. 2) of a planar boundary BL that passes through the longitudinal center of the contact surface 3s. The large number of second inclined holes 32 are disposed on the other side (right side in FIG. 2) of the boundary BL. In this embodiment, the first and second inclined holes 31, 32 are disposed on the contact surface 3s at approximately equal intervals in the extension direction of the boundary BL (the lateral direction of the contact surface 3s) and in the direction perpendicular to the boundary BL (the longitudinal direction of the contact surface 3s). Note that the boundary BL does not necessarily have to be flat and may be curved.

[0014] As shown in FIG. 3 , the first and second inclined holes 31, 32 are extremely shallow, blind holes recessed from the contact surface 3s of the insert member 3 with the casting portion 2 and extending at an angle relative to the contact surface 3s. More specifically, each first inclined hole 31 is inclined so as to move away from the boundary BL as it moves away from the contact surface 3s in the depth direction. In contrast, each second inclined hole 32 is inclined in the opposite direction to the first inclined hole 31, moving away from the boundary BL as it moves away from the contact surface 3s in the depth direction. As can be seen from FIG. 4 , each first inclined hole 31 and each second inclined hole 32 extends generally parallel to a direction perpendicular to the boundary BL in a plan view. Furthermore, as shown in FIGS. 3 and 4 , each first inclined hole 31 and each second inclined hole 32 tapers as it moves away from the contact surface 3s in the depth direction.

[0015] Each of the first inclined holes 31 and each of the second inclined holes 32 is formed in the contact surface 3s of the insert member 3 by irradiating the contact surface 3s with a short-pulse laser, such as a nanosecond laser or a femtosecond laser. The average output of the short-pulse laser is, for example, 1 W, and the peak output is, for example, 100 kW. In this embodiment, the average inner diameter φ (see FIG. 2 ) of the first and second inclined holes 31, 32 in the contact surface 3s is, for example, 50 μm, and the average depth d is, for example, 100 μm. The inclination angle θ1 of each of the first inclined holes 31 with respect to the contact surface 3s is, for example, 45°, and the inclination angle θ2 of each of the second inclined holes 32 with respect to the contact surface 3s is, for example, 135°. That is, each of the first inclined holes 31 is formed by irradiating the contact surface 3s with the short-pulse laser at an incident angle of 45°, and each of the second inclined holes 32 is formed by irradiating the contact surface 3s with the short-pulse laser at an incident angle of 135°.

[0016] The average spacing between adjacent first inclined holes 31, the average spacing between adjacent second inclined holes 32, and the average spacing between adjacent first and second inclined holes 31, 32 across the boundary BL are set to be smaller than the average inner diameter φ of the first and second inclined holes 31, 32 on the contact surface 3s, within the range that can be achieved by laser processing. Furthermore, a plurality of protrusions 33 extending along the entire periphery or part of the periphery of each of the first inclined holes 31 and each of the second inclined holes 32 are formed on the contact surface 3s of the insert member 3 by irradiating the contact surface 3s with a short pulse laser.

[0017] The insert casting 1 including the insert member 3 described above is manufactured by placing the insert member 3 as an insert in a mold (not shown), pouring molten metal such as an aluminum alloy into the mold, and solidifying it. Specifically, prior to integration with the cast portion 2 by casting, the insert member 3 has a number of first and second inclined holes 31, 32 pre-formed on a contact surface 3s that will come into contact with the cast portion 2. During the manufacture of the insert casting 1, a portion of the molten metal flows into each of the first inclined holes 31 and each of the second inclined holes 32 of the insert member 3 and solidifies and shrinks in each of the first inclined holes 31 and each of the second inclined holes 32. The metal in each of the first inclined holes 31 and each of the second inclined holes 32 is then forced into intimate contact with the region of the inner circumferential surface of the corresponding first or second inclined hole 31, 32 on the contact surface 3s side (the opposite side from the boundary BL) due to stresses generated and remaining in response to solidification and shrinkage. As a result, in the insert cast product 1, it is possible to improve the bonding strength between the cast portion 2 and the member 3 to be inserted into the insert cast product.

[0018] Furthermore, in the insert cast product 1, the insert member 3 includes a plurality of protrusions 33 extending along at least a portion of the periphery of the corresponding first or second inclined hole 31, 32. As a result, the protrusions 33 on the periphery of each first inclined hole 31 and each second inclined hole 32 bite into the cast portion 2 and function as wedges (anchors), which makes it possible to further improve the bonding strength between the cast portion 2 and the insert member 3.

[0019] Furthermore, the insert cast part 1 includes a plurality of first inclined holes 31 arranged on one side of a boundary BL set with respect to the contact surface 3s of the insert workpiece 3 so as to be inclined in the same direction as each other, and a plurality of second inclined holes 32 arranged on the other side of the boundary BL so as to be inclined in the same direction as each other but in the opposite direction to the plurality of first inclined holes 31. This allows the stress acting on the metal that has solidified and shrunk in the first inclined holes 31 and the stress acting on the metal that has solidified and shrunk in the second inclined holes 32 to be in opposite directions, thereby further improving the bonding strength between the casting part 2 and the insert workpiece 3.

[0020] In the insert-cast product 1, each first inclined hole 31 is inclined so as to move away from the boundary BL as it moves away from the contact surface 3s in the depth direction, and each second inclined hole 32 is inclined in the opposite direction to the first inclined hole 31 so as to move away from the boundary BL as it moves away from the contact surface 3s in the depth direction, but this is not limited to this. That is, as shown in FIG. 5 , each first inclined hole 31 in the insert material 3 may be inclined so as to move closer to the boundary BL as it moves away from the contact surface 3s in the depth direction, and each second inclined hole 32 may be inclined in the opposite direction to the first inclined hole 31 so as to move closer to the boundary BL as it moves away from the contact surface 3s in the depth direction. Even in this embodiment, the stress acting on the metal that solidifies and shrinks in the first inclined hole 31 and the stress acting on the metal that solidifies and shrinks in the second inclined hole 32 can be in opposite directions, thereby further improving the bonding strength between the casting 2 and the insert-cast product 3. Furthermore, the first and second inclined holes 31, 32 may be formed in the contact surface 3s of the insert member 3 so as to be inclined in the same direction.

[0021] Furthermore, in the insert cast product 1, the first and second inclined holes 31, 32 are formed to taper as they move away from the contact surface 3s in the depth direction. As a result, when manufacturing the insert cast product 1, the molten metal that flows into each of the first inclined holes 31 and each of the second inclined holes 32 solidifies sequentially from the bottom side of each of the first inclined holes 31 and each of the second inclined holes 32, which improves the bonding strength of the metal and makes it possible to suppress the occurrence of cracks in the metal.

[0022] Furthermore, in the insert cast product 1, the average spacing between adjacent first inclined holes 31, the average spacing between adjacent second inclined holes 32, and the average spacing between adjacent first and second inclined holes 31, 32 across the boundary BL are set to be smaller than the average inner diameter φ of the first and second inclined holes 31, 32 at the contact surface 3s, within the range that can be achieved by laser processing. In this way, by densely arranging the first and second inclined holes 31, 32 relative to the contact surface 3s, the molten metal flowing into each of the first inclined holes 31 and each of the second inclined holes 32 promotes a temperature rise of the insert cast product 3, and the molten metal flowing into each of the first inclined holes 31 and each of the second inclined holes 32 can be gradually cooled.

[0023] In the insert casting 1, the average inner diameter φ of the first and second inclined holes 31, 32 is, for example, 50 μm, and the average depth d is, for example, 100 μm, but these are not limited thereto. That is, depending on the area of ​​the contact surface 3s of the insert casting member 3, the average inner diameter φ of the first and second inclined holes 31, 32 may be set within a range of, for example, 30 μm to 100 μm, and the average depth d of the first and second inclined holes 31, 32 may be set within a range of, for example, 30 μm to 300 μm. Furthermore, the inclination angle θ1 of each first inclined hole 31 relative to the contact surface 3s may be set within a range of, for example, 30° to 75°, and the inclination angle θ2 of each second inclined hole 32 relative to the contact surface 3s may be set within a range of, for example, 105° to 150°. Furthermore, the first and second inclined holes 31, 32 do not necessarily have to be formed over the entire contact surface 3s, but may be formed in a part of the contact surface 3s.

[0024] 6, the insert member 3B including the contact surface 3s may be integrated with the cast portion 2B so that one end is embedded in the cast portion 2B and the other end protrudes from the cast portion 2B. The cast portions 2, 2B and the insert members 3, 3B may be formed from a metal other than an aluminum alloy. Furthermore, the cast portions 2, 2B are not limited to those forming a torque box or a suspension tower of a vehicle, and the insert members 3, 3B are not limited to those forming a side member of a vehicle.

[0025] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present disclosure. Furthermore, the above-described embodiment is merely a specific form of the invention described in the Summary of the Invention, and does not limit the elements of the invention described in the Summary of the Invention. [Industrial Applicability]

[0026] The invention of the present disclosure can be used in industries such as the manufacturing of insert moldings. [Explanation of symbols]

[0027] 1,1B: Inserted part; 2,2B: Casting part; 3,3B: Inserted part; 3s: Contact surface; 31: First inclined hole; 32: Second inclined hole; 33: Protrusion; BL: Boundary.

Claims

1. In an insert casting product including a cast part and an insert member which are integrated by insert casting, An insert-cast product having a plurality of inclined holes each recessed from a contact surface with the casting portion of the insert member and extending at an angle relative to the contact surface.

2. The insert molding product according to claim 1, The insert member includes a plurality of protrusions extending along at least a portion of the periphery of each of the plurality of oblique holes.

3. The insert molding product according to claim 1 or 2, The plurality of inclined holes include a plurality of first inclined holes disposed on one side of a boundary set with respect to the contact surface of the insert casting, and a plurality of second inclined holes disposed on the other side of the boundary, The plurality of first inclined holes are inclined in the same direction as each other, and the plurality of second inclined holes are inclined in the same direction as each other and in the opposite direction to the plurality of first inclined holes.

4. The insert molding product according to claim 1 or 2, The inclined hole is an insert casting formed to taper as it moves away from the contact surface in the depth direction.

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