Influence of Tungsten Nanopowders on Enhancing the Aging Behavior of a Copper–Chromium Alloy

Abstract

Copper–chromium alloys are a class of high-strength high-conductivity copper alloys. However, limited by the copper–chromium (Cu–Cr) phase diagram, the strength of copper–chromium (Cu–Cr) alloys by precipitation-hardening has reached a certain limit. Suitable nanoparticles incorporating into copper–chromium (Cu–Cr) alloys, i.e., nano-treating, are expected to modify the aging behavior and further improve their properties. In this study, copper–chromium (Cu–Cr) alloy containing tungsten (W) nanoparticles was cast. The aging behavior of the nano-treated Cu-Cr and Cu–Cr counterparts is assessed. Tungsten (W) nanoparticles accelerate the precipitation, leading to a significant reduction in the peak aging time. Besides, the microhardness of the nano-treated copper–chromium (Cu–Cr) is increased over Cu–Cr after 45-min aging. Cold rolling can further enhance the microhardness of the nano-treated copper–chromium (Cu–Cr). Moreover, the nano-treated sample exhibits a much improved thermal stability. Thus, nano-treating the copper–chromium (Cu–Cr) alloy by tungsten (W) nanoparticles is promising to break the limits of current copper–chromium (Cu–Cr) alloys.