High-entropy-alloy-based self-lubricating composite and preparation method thereof

Abstract

The invention discloses a high-entropy-alloy-based self-lubricating composite and a preparation method thereof. The preparation method of the high-entropy-alloy-based self-lubricating composite includes the steps that a four-element high-entropy alloy CoCrFeNi is used as a matrix, a solid lubricant is used as a lubricating phase, the CoCrFeNi and the solid lubricant are ball-milled and mixed and then deposited on a metal substrate through cold spraying to form a sedimentary body, the sedimentary body is subjected to friction stir machining through a stirring head, and the high-entropy-alloy-based self-lubricating composite is obtained, wherein the mass ratio of the CoCrFeNi to the solid lubricant is (2.3-4):1. According to the self-lubricating composite, the high-entropy alloy CoCrFeNi isused as the matrix, excellent mechanical performance of the high-entropy alloy overcomes losses of strength and toughness caused by adding of the solid lubricant, and therefore the prepared high-entropy-alloy-based self-lubricating composite keeps good self-lubricating capacity and has excellent mechanical performance.

Description

technical field [0001] The invention belongs to the technical field of self-lubricating composite material preparation, and in particular relates to a high-entropy alloy-based self-lubricating composite material and a preparation method thereof. Background technique [0002] Generally, metal-based self-lubricating composite materials are widely used in mechanical parts that are difficult to lubricate with conventional grease or in mechanical equipment that serve in harsh working conditions such as high speed, heavy load, high temperature, vacuum, and cryogenic. In order to obtain a lower coefficient of friction, metal-based self-lubricating composites generally need to add more solid lubricants, however, too much solid lubricants will reduce the mechanical properties of the composites. At present, most researchers prepare metal-based self-lubricating composites by sacrificing the strength of composites to improve their self-lubricating ability, which severely limits the appl...

AI Technical Summary

Problems solved by technology

The preparation of high-entropy alloy-based self-lubricating composites and their additive manufacturing are hotspots for future industrial needs. However, due to the high melting point of high-entropy alloys and the high melting point of most solid lubricants, traditional additive manufacturing Technology (selective laser cladding, selective laser sintering, and electron beam fuse forming, etc.) to prepare high-entropy alloy-based self-lubricating composite materials consumes a lot of energy on the one hand, and on the other hand, there are many defects in the solidification structure and low performance.

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