On the precipitation strengthening of Cu–2.6Ni–0.6Si–0.6Cr bronzes

Resumo

A thermodynamic simulation of phase equilibria in the Cu–Ni–Si–Cr system has been carried out using a FactSage program package (version 7.0). The structure and phase composition of the Cu–2.6Ni–0.6Si–0.6Cr bronze have been studied in the quenched and additionally aged (under various conditions) states. Precipitates of the chromium silicide Cr₃Si have been revealed in the alloy both in the quenched and aged states. Particles of nickel silicide Ni₂Si 0.05–0.5 μm in size appear upon the precipitation hardening both homogeneously and heterogeneously (on particles of previously formed chromium silicides). The microhardness (HV) and the electrical resistivity of the experimental samples have been determined after conducting processes of precipitation strengthening.