3D printing three-dimensional network structure graphite/metal composite material and its preparation method by atmospheric pressure casting

Abstract

The invention provides a 3D printing three-dimensional network structure graphite / metal composite material with good friction reduction, shock absorption, thermal conductivity, electrical conductivity, strength, toughness, low density and thermal expansion and its atmospheric pressure casting Infiltration preparation method. The composite material is a gradient / non-gradient metal-based composite material composed of graphite and metal in an interconnected network structure connected in three-dimensional space, the thickness of the graphite layer is controllable, and the graphite network structure can be changed as required. The preparation method is as follows: (1) preparing a mixed powder of flake graphite powder and metal powder; (2) using a laser selective sintering method to 3D print a graphite / metal composite network structure preform; (3) using an atmospheric pressure casting infiltration method to prepare a three-dimensional network Structural graphite / metal composites. The invention can be used in the fields of machinery, metallurgy, environmental protection, aerospace, electronics and the like as materials such as self-lubricating friction reduction, vibration reduction / sound insulation, high-efficiency heat conduction and electrical conduction.

Description

technical field [0001] The invention relates to the technical fields of 3D printing (additive manufacturing), metal matrix composite materials and atmospheric casting, in particular to a 3D printing three-dimensional network structure graphite / metal composite material and a method for preparing it by atmospheric casting and infiltration. Background technique [0002] Three-dimensional Co-continuous Network Metal Matrix Composite (or Interpenetrating Network Metal Matrix Composite, INMMC for short) is a new type of composite material that has been paid more and more attention by domestic and foreign material researchers in the past ten years. field. This composite material has a completely different spatial topology from traditional composite materials, that is, the metal matrix phase and the composite phase (or modified phase) are continuous (connected) in three-dimensional space, showing an interwoven network structure. This topological structure in which the two phases ar...

AI Technical Summary

Problems solved by technology

The conventional graphite particle or graphite fiber modified metal composite material stirring casting preparation method is used to prepare graphite / metal matrix composite material. Although the production cost is low, it is not only difficult to control the distribution uniformity of graphite, but also difficult to increase the amount of graphite added (graphite is very easy to Floating in molten metal to produce composition segregation)

The mixed powder laser melting method (SLM method) or sintering method (SLS method) of graphite and metal is used to prepare graphite / metal compact composite materials. Although the distribution uniformity of graphite can be improved, the amount of graphite added can also be greatly increased (such as figure 1 ), but the production efficiency is low and the cost is high

[0004] The above methods are all due to the fact that the graphite particles are basically in a dispersed distribution, the graphite distribution pattern is uncontrollable, and it is difficult for the graphite phase to connect to form a continuous network structure, so it is difficult to obtain the characteristics of a network structure composite material with two phases interconnected, and its vibration reduction and friction reduction , thermal conductivity, electrical conductivity and other performance improvements are limited

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