Experimental producing of Cu–Cr–N composite alloys and thermodynamic modeling of their phase composition

Abstract

Composite Cu–Cr–N alloys were obtained in situ under vibration of “copper melt – chromium powder” compositions before their crystallization. Two types of alloys were prepared, where chromium powder was freely dispersed or compacted into a tablet. Atmospheric nitrogen was used as a source of chromium nitrides in the alloys. The microstructure of the alloys is represented by a copper matrix hardened with chromium particles and numerous inclusions of non-stoichiometric chromium nitrides Cr2N1–x. Thermodynamic modeling showed that the composition and quantities of chromium nitrides in the Cu–Cr–N alloy depend on the partial pressure of nitrogen above the melt.