Influence of aging temperature and time on hardness and electrical conductivity of Cu–Cr alloys

Abstract

Specimens of cold-rolled Cu–0·44Cr and Cu–0·94Cr were solution treated and water quenched. Their hardness and electrical conductivity were measured after quenching and aging. Thin foils of Cu–0·94Cr were prepared and examined in the electron microscope. The sizes of coherent particles in the foils were measured and from these results it was deduced that particle growth is controlled by volume diffusion. Both coherently precipitated and non-dissolved chromium particles with a bee lattice were observed in aged Cu–0·94Cr. Empirical formulae for the influence of aging temperature and time on hardness and coruiuctivity were established.