A kind of heterogeneous gradient composite material and its preparation method

Abstract

The invention provides a heterogeneous gradient composite material and a preparation method thereof. The preparation method comprises the steps that an aluminum base composite material is manufacturedinto a slab, then the aluminum base composite material slab and aluminum-silicon alloy powder are laid in sequence, and finally, the aluminum base alloy composite material and aluminum-silicon alloyare tightly combined to obtain the heterogeneous gradient composite material by pressure sintering. By preparing the aluminum base composite slab in advance without cold pressing and molding, high volume fraction can be obtained, thermal expansion coefficient can be reduced, the thickness and shape of an aluminum base composite layer are controlled easily, and the repeatability of the process is ensured; and the sintering performance of the aluminium-silicon alloy is good, pressure sintering with powder direct laying can reduce the forming process and reduce the cost, the using requirements can be better met, and the stability of the process is ensured.

Description

technical field [0001] The invention relates to the technical field of material engineering, in particular to a heterogeneous gradient composite material and a preparation method thereof. Background technique [0002] Electronic packaging materials are base materials used to carry electronic devices and their interconnections, and play the roles of mechanical support, sealing environment protection, signal transmission, heat dissipation and shielding. [0003] Metal matrix composites organically combine a metal matrix with good thermal conductivity and plastic deformation properties and a reinforcement with a low thermal expansion coefficient and high strength. It is a kind of thermal conductivity and thermal expansion coefficient. Wide range of controllable electronic packaging materials, capable of packaging various chips and substrate materials. Among them, the aluminum-based composite material has excellent thermophysical properties, low density and high strength, and i...

AI Technical Summary

Problems solved by technology

When using aluminum-based heterogeneous materials (such as aluminum-silicon alloy and aluminum-silicon carbide) to make graded functional materials, the applicant has previously tried to combine aluminum-silicon alloy and aluminum-silicon carbide composite materials or aluminum-silicon alloy and aluminum-diamond composite materials. The powders are cold-pressed into plates and then alternately laid up and hot-pressed into gradient materials. However, after such treatment, due to the mutual penetration and extrusion of the aluminum-silicon alloy layer and the aluminum-silicon carbide layer or the aluminum diamond layer, it is difficult to control the final The thickness of the aluminum silicon carbide or aluminum diamond layer in the gradient material, because the aluminum silicon carbide or aluminum diamond layer needs to play the role of heat conduction and mechanical shock resistance in electronic packaging materials, if its thickness is uncontrollable, it will seriously affect the electronic packaging material. Thermal and mechanical properties and process properties

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