Method for preparing high-entropy alloy coating

Abstract

The invention relates to the field of multi-principal element high-entropy alloy materials and in particular relates to a method for preparing a high-entropy alloy coating, belonging to the field of coating preparation. The method for preparing the high-entropy alloy coating comprises the following steps: pretreating a substrate, so that the surface of the substrate is clean and flat; preparing high-entropy alloy powder, uniformly mixing, and adding 3-6wt% of organic solution in the alloy powder; uniformly mixing the organic solution and the high-entropy alloy powder, and preparing into paste; uniformly coating the pasty alloy powder on the treated substrate, wherein the thickness of the coating layer is 0.3-6mm; baking the treated coating layer and substrate in an oven at the temperature of 55-80 DEG C for 20-30 hours; cladding the coating layer on the surface of the substrate through gas tungsten arc welding. According to the method for preparing the high-entropy alloy coating, the high-entropy alloy coating with the thickness of 0.3-6mm can be prepared, a heat affected zone to the substrate in the preparation process is small, and the coating is uniform in distribution and firmly bound to the base material.

Description

technical field [0001] The invention relates to the field of multi-principal high-entropy alloy materials, in particular to a method for preparing a high-entropy alloy coating, which belongs to the field of coating preparation. Background technique [0002] High-entropy alloy refers to a new type of alloy that contains 5 to 13 alloying elements, each element content is between 5% and 35%, and can form a high-entropy solid solution. There are no alloy elements with a content of more than 50% in high-entropy alloys, and there is no distinction between major elements and minor elements in the entire alloy system. Through appropriate alloy composition design, high-entropy alloys can exhibit a multivariate collective effect, that is, the disorder effect of atomic arrangement. The study found that the high-entropy alloy system reflects a multi-element collective effect, presents a simple crystal phase, and has the characteristics of high strength, high hardness, high wear resista...

AI Technical Summary

Problems solved by technology

(2) Lattice distortion effect, due to the difference in atomic radius between elements, causes lattice distortion, affects the physical and chemical properties of the alloy; leads to solid solution strengthening, affects the electrical conductivity, magnetism, thermal conductivity, etc. of the alloy

(3) Diffusion retardation effect, the synergistic diffusion between various elements is very difficult, and serious lattice distortion will slow down the diffusion rate of elements, so the phase separation is very slow at high temperature, and even inhibited and delayed to low temperature

The preparation method of the above-mentioned plasma cladding high-entropy alloy coating adopts a spray gun to send powder, and sprays the alloy powder on the surface of the substrate. If the surface is exposed, the base material is not completely covered by the coating, and it needs to be repeated several times to realize that the base material surface is completely covered by the coating, which will increase the thickness of the coating, generally more than 8mm; at the same time, use a spray gun to feed powder , alloy powders of different densities will gradually separate during the process of moving to stop, resulting in uneven distribution of alloy powder on the surface of the substrate, which in turn leads to different properties of the prepared coating; in addition, the input heat of plasma cladding large, resulting in a large amount of thermal deformation of the substrate; the alloy powder sent by the powder spray gun is dry powder, the coating obtained after cladding has high porosity and poor density, and the coating is easy to fall off from the substrate surface; and plasma cladding requires a large Special equipment, high preparation cost

Images