Formation of metal composites by detonation spray of powder mixtures

Abstract

The feasibility study of elaboration of metal composite coatings by detonation spray using the blends of iron, nickel, copper, cobalt, and aluminum powders was performed using different spray modes. The numerical simulation of particle parameters showed that the particles formed the coating in solid, semi-molten, or molten state depending on the spraying modes, particle material, and particle size. It was shown that successful formation of the coating containing all powder mixture components could be achieved in case of proper optimization of spraying parameters. Obtained Fe-Co-Ni, Fe-Co-Ni-Cu, and Fe-Co-Ni-Cu-Al coatings had the uniform lamellae structure. However, the composition of the coatings differed from the initial powder mixture composition due to different deposition efficiencies of the powders. It was also found the mutual influence of blend components on bonding. In particular, the deposition efficiency of iron particles was probably affected by copper.

A Feasibility Study of High-Entropy Alloy Coating Deposition by Detonation Spraying Combined with Laser Melting

“…As a result, a fraction of the iron particles could cool down in the gas jet after the barrel exit and impact the substrate in the solid state. A similar conclusion was drawn in our previous work [11].…”

“…In our previous work, it was shown that the highest coating density and the highest powder deposition efficiency are achieved when spraying of the mixtures is performed in the "hot" spraying mode [11]. In this mode, the particle temperature is higher than the melting point of the metals contained in the mixture [11]. In the present work, the experiments were also performed in the "hot" mode.…”

“…The deposition efficiency of the mixture components during detonation spraying should be given particular attention. As shown in [11], the efficiency with which particles attach to the surface, depends not only on the detonation spraying parameters, but also on the features of the interaction of the particles of different components with each other during spraying. For example, the deposition efficiencies of iron during detonation spraying of Mix 1, Mix 2 and Mix 3 were different under the same spraying parameters.…”

“…The dilution of the explosive charge by nitrogen allowed for the temperature control of the detonation products. In our previous work, it was shown that the highest coating density and the highest powder deposition efficiency are achieved when spraying of the mixtures is performed in the "hot" spraying mode [11]. In this mode, the particle temperature is higher than the melting point of the metals contained in the mixture [11].…”

“…Most metals can be deposited by detonation spraying [8][9][10]. Previous studies showed that metal composite coatings containing three, four or five components can be deposited successfully by detonation spraying [11]. A proper adjustment of the precursor coating composition and optimization of the post-treatment procedure could potentially allow fabricating HEA coatings with almost any combination of metallic elements.…”