Evolution of microstructure and properties of Fe-Cu, manufactured by electron beam additive manufacturing with subsequent friction stir processing

Abstract To improve the microstructure, microhardness and wear resistance of the gradient zone, the friction stir processing (FSP) of Fe-Cu bimetal, manufactured by electron-beam additive manufacturing (EBAM), is used for the first time. Analysis of the microstructure of the stir zone showed a completely recrystallized grain structure consisting of supersaturated solid solutions of γ-Fe (≤10.8 at.%) in Cu and Cu (≤16 at.%) in γ-Fe, with a decrease in the grain size more than 98% compared to the untreated sample. After FSP the microhardness increased on average by 50%, and the value of the friction coefficient decreased by 25%.