The combination of precipitation and dispersion hardening in powder metallurgy produced Cu-Ti-Si alloy

Microstructure and microhardness properties of precipitation hardened Cu-Ti and precipitation/dispersion hardened Cu-Ti-Si alloys have been analyzed. Cu-1.2Ti and Cu-1.2Ti-3TiSi2 (wt.%) atomized powders were characterized before and after consolidation by HIP (Hot Isostatic Pressing). Rapidly solidified powders and HIP-ed compacts were subsequently subjected to thermal treatment in hydrogen at temperatures between 300 and 600 °C. Compared to Cu-Ti powder particles and compacts, obtained by the same procedure, the strengthening effect in Cu-1.2Ti-3TiSi2 powder particles and compacts was much greater. The binary and ternary powders both reveal properties superior to those of Cu-1.2Ti and Cu-1.2Ti-3TiSi2 compacts. Microhardness analysis as a function of the aging temperature of Cu-1.2Ti-3TiSi2 alloy shows an interaction between precipitation and dispersion hardening which offers possibilities for an application at elevated temperatures.