Aluminum-silicon carbide composite and production method therefor

Patent metadata

Field	Value
Publication number	US-2017236767-A1
Application number	US-201515500210-A
Country	US
Kind code	A1
Filing date	Jul 29, 2015
Priority date	Jul 31, 2014
Publication date	Aug 17, 2017
Grant date	—

Abstract

An aluminum-silicon carbide composite including flat-plate-shaped composited portion containing silicon carbide and an aluminum alloy, and aluminum layers containing an aluminum alloy provided on both plate surfaces of composited portion, wherein circuit board is mounted on one plate surface and the other plate surface is used as heat-dissipating surface, wherein: the heat-dissipating-surface-side plate surface of the composited portion has a convex curved shape; the heat-dissipating-surface-side aluminum layer has a convex curved shape; ratio (Ax/B) between the average (Ax) of the thicknesses at the centers on opposing short sides of outer peripheral surfaces and thickness (B) at central portions of the plate surfaces satisfies the relationship: 0.91≦Ax/B≦1.00; and a ratio (Ay/B) between the average (Ay) of the thicknesses at the centers on opposing long sides of outer peripheral surfaces and thickness (B) at central portions of the plate surfaces satisfies the relationship: 0.94≦Ay/B≦1.00 and production method therefor.

First claim

1 . An aluminum-silicon carbide composite comprising a flat-plate-shaped composited portion containing silicon carbide and an aluminum alloy, and aluminum layers containing an aluminum alloy provided on both plate surfaces of the composited portion, wherein a circuit board is mounted on one of the plate surfaces and the other plate surface is used as a heat-dissipating surface, and wherein:
the heat-dissipating-surface-side plate surface of the composited portion has a convex curved shape; the heat-dissipating-surface-side aluminum layer has a convex curved shape; a ratio (Ax/B) between the average (Ax) of the thicknesses at the centers on opposing short sides of outer peripheral surfaces and the thickness (B) at central portions of the plate surfaces satisfies the relationship: 0.91≦Ax/B≦1.00; and a ratio (Ay/B) between the average (Ay) of the thicknesses at the centers on opposing long sides of outer peripheral surfaces and the thickness (B) at central portions of the plate surfaces satisfies the relationship: 0.94≦Ay/B≦1.00.

2 . The aluminum-silicon carbide composite according to claim 1 , wherein, when a circuit board is mounted, the amount of curvature Cx for every 10 cm in the short-side direction of the outer peripheral surfaces satisfies the relationship:
−10 μm≦Cx≦30 μm; and the amount of curvature Cy for every 10 cm in the long-side direction of the outer peripheral surfaces satisfies the relationship: −10 μm≦Cy≦40 μm.

3 . The aluminum-silicon carbide composite according to claim 1 , wherein the lengths of the short sides and the long sides of the outer peripheral surfaces are equal; and
a ratio (AB) between the average (A) of the thicknesses at the centers on opposing sides of outer peripheral surfaces and the thickness (B) at central portions of the plate surfaces satisfies the relationship: 0.91≦A/B≦1.00.

4 . The aluminum-silicon carbide composite according to claim 1 , wherein the average thickness of the aluminum layer on the surface on which the circuit board is mounted is 0.1 mm to 0.3 mm, and the thickness difference of the aluminum layer at said surface is 0.1 mm or less.

5 . The aluminum-silicon carbide composite according to claim 1 , wherein the difference between the average thickness of the aluminum layer on the surface on which the circuit board is mounted and the average thickness of the aluminum layer on the heat-dissipating surface is 50% or less of the average thickness of the thicker aluminum layer.

6 . The aluminum-silicon carbide composite according to claim 1 , having a thermal conductivity at 25° C. of 180 W/mK or more, and a coefficient of thermal expansion at 150° C. of 10×10 −6 /K or less.

7 . A method for producing the aluminum-silicon carbide composite according to claim 1 , the method comprising:
a step of forming a flat-plate-shaped silicon carbide porous body; a step of machining one plate surface of the silicon carbide porous body so as to form a convex curved shape; a step of impregnating the silicon carbide porous body with an aluminum alloy so as to produce an aluminum-silicon carbide composite comprising a flat-plate-shaped composited portion containing silicon carbide and an aluminum alloy, and aluminum layers, containing an aluminum alloy, provided on both plate surfaces of the composited portion; and a step of machining the aluminum layer on the side of the silicon carbide porous body having the surface that has been machined to a convex curved shape, so as to form a heat-dissipating surface having a convex curved shape.

Assignees

• Denka Company Ltd

Inventors

• Miyakawa Takeshi
• KINO Motonori
• Hirotsuru Hideki

Classifications

• H10W40/255

  having a laminate or multilayered structure, e.g. direct bond copper [DBC] ceramic substrates · CPC title

• H10W40/226

  characterised by projecting parts, e.g. fins to increase surface area (leadframes for cooling H10W70/461) · CPC title

• H10W40/10

  Arrangements for heating · CPC title

• H10W40/257 Primary

  having a heterogeneous or anisotropic structure, e.g. powder or fibres in a matrix, wire mesh or porous structures (H10W40/254, H10W40/251 take precedence) · CPC title

• B22D17/00

  Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure · CPC title