Effects of multiple trace alloying elements on the microstructure and properties of Cu-4 wt% Ti alloys

Effects of multiple trace alloying element Fe and Cr addition on the solid solution-treated Cu-4 wt% Ti alloys were studied with respect to microstructure and mechanical properties. It was elucidated that the addition of trace alloying elements results in the formation of intermetallic phase CuTi, lowering the titanium content of Cu solid solution phase, and refining the microstructure. The contributions of different strengthening mechanisms were calculated, which are in good agreement on experimental results. It turns out that the solute solution strengthening in Cu-Ti alloys plays a crucial role, even though the fine grain size and precipitation strengthening mechanism are contributed to the strength of Cu-Ti-Cr -Fe alloys. Therefore, the Cu-Ti-Cr-Fe alloys exhibits lower strength and higher elongation compared with Cu-4 wt% Ti alloys. However, Cu-Ti-Cr-Fe alloys show a great potential to balance the mechanical properties and electrical conductivity during aging treatment as the titanium content decreases in the Cu matrix, and the strength is higher than that of others in previous study.