The effect of fe additions on the embrittlement of Cu-Bi alloys

The effect of iron additions on the embrittlement of Cu-Bi alloys was studied by monitoring the ductility and grain boundary chemistry of embrittled specimens as a function of iron content. Mechanical properties improved for the same embrittling heat treatment as the bulk iron level increased, and this was correlated with a decrease in bismuth segregation to the grain boundaries. No iron was detected segregated to the boundaries, and several possible mechanisms were proposed to explain the beneficial effect of the iron additions. It was also found that approximately 70 min at 530°C is required to attain equilibrium for segregation of bismuth to the grain boundaries, and a diffusion coefficient derived from this data was found to be reasonable for bulk diffusion of bismuth in copper.