Heat-conductive composite material sheet and preparation method thereof

Abstract

Disclosed is a heat conductive composite material sheet (100), which comprises a first aluminum alloy layer (110), at least one graphite sheet (120), an aluminum alloy frame (130) and a second aluminum alloy layer (140), wherein the aluminum alloy frame (130) is provided with at least one opening (131), the graphite sheet (120) is positioned in the opening (131) of the aluminum alloy frame (130), the aluminum alloy frame (130) and the graphite sheet (120) are clamped between the first aluminum alloy layer (110) and the second aluminum alloy layer (140), the first aluminum alloy layer (110) is diffusively bonded with the graphite sheet (120) and the aluminum alloy frame (130), the second aluminum alloy layer (140) is diffusively bonded with the graphite sheet (120) and the aluminum alloy frame (130), and the graphite sheet (120) is coated with the first aluminum alloy layer (110), the second aluminum alloy layer (140) and the aluminum alloy frame (130) as a whole. The present invention also provides a fabrication method of the heat conductive composite material sheet. The heat conductive composite material sheet provided by the present invention and the fabrication method thereof can connect high heat conductive aluminum alloy to graphite and have a low production cost.

Description

technical field [0001] The invention relates to the technical field of heat control, in particular to a heat-conducting composite material sheet with high heat-conducting properties and a manufacturing method thereof. Background technique [0002] In the heat dissipation structure of electronic components, forged aluminum alloy materials with high strength and high thermal conductivity, such as American brand 6XXX series (6061, 6063), and domestic brand LD series aluminum alloys, are often used for heat dissipation fins, heat sinks, etc. Shen frame and other structures. 6XXX series aluminum alloys are a kind of medium-high strength aluminum alloys that can be strengthened by heat treatment. With its high specific strength and good thermal conductivity, it can prepare a variety of structural or functional aluminum alloy components with special purposes, and has a wide range of applications in aerospace, transportation, electronics, architectural decoration, and sports equipm...

AI Technical Summary

Problems solved by technology

[0004] The compatibility of aluminum and graphite is very poor, which includes two problems. First, the wettability of liquid aluminum and graphite is poor, and the metal aluminum liquid cannot spread on the graphite substrate.

Secondly, when the synthesis temperature exceeds 500°C, a chemical reaction will occur between aluminum and carbon to form a brittle carbide reaction layer. With the further increase of the synthesis temperature, the chemical reaction will aggravate, seriously weakening the thermal conductivity of graphite itself, and also causing Degradation of Composite Properties

[0005] Traditional hot pressing can produce high-performance materials, but for materials such as pure nitrides, carbides, oxides or borides with a theoretical density close to 100%, especially when high volume fractions of high thermal conductivity ceramics or diamonds, graphite, etc. When mixed with metal matrix, it is difficult to prepare by powder sintering densification or liquid phase processing technology

Moreover, the productivity of this technology is quite limited, the heat treatment temperature is as high as 2200 ° C, the cycle time is usually 6 hours or 12 hours, the production process is complicated, and the production cycle is long

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