INVESTIGATION OF THE EFFECT OF HEAT TREATMENT ON Cu – Al ALLOYS OBTAINED BY WIRE-ARC ADDITIVE MANUFACTURING

Abstract

By methods of optical, scanning and transmission electron microscopy, studies have been carried out to establish the influence of Al, Si andMg on the formation and change of the structure, phase composition and distribution of elements of Cu–Al alloys obtained by wire-arc additive manufacturing with cold metal transfer, and after their heat treatment. The main factors determining the mechanical behavior of Cu-Al alloys after the addition of Si and Mg and their heat treat- ment are determined and analyzed. It is shown that the increased strength and hardness of the Cu-Al alloy is explained by grain grinding and the formation of particles of the second phases between the layers of the deposited metal. The features of the distribution of the main elements (Cu, Al) and secondary elements (Si, Mg) in the process of wire-arc additive manufacturing are revealed. Recently, studies of the Cu-Al alloy have been carried out, which have shown that Al as a solid solution element in the Cu-Al alloy can increase the formation of deformation twins and the density of dislocations. In addition, it was found that the addition of micro-alloying elements to the Cu–Al alloy significantly improves its me- chanical properties. The kinetics of the growth of intermetallic compounds such as CuAl2, Cu9Al4, Cu3Al in Cu–Al casting alloys has been studied. As a result of the complex of technological measures, the modes of obtaining additive billets of Si–Al, Cu–Al–Si and Cu–Al–Si–Mg alloys were selected. Technological equipment has been improved to obtain blanks as part of the work. The microstructure, phase composition and mechanical properties of Si–Al, Cu–Al–Si and Cu–Al–Si–Mg alloys obtained bywire-arc additivemanufacturing using coldmetal transfer technology are investigated.