Effect of Al(Cr) Content on the Distribution of Al_2O_3(Cr_2O_3) Particles Formed by Internal Oxidation

摘要

This investigation was conducted to study the effect of Al(Cr) content in Cu-Al(Cr) pre-alloyed powders on the distribution of Al_2O_3(Cr_2O_3) particles formed by internal oxidation. The results show that the distribution of Al_2O_3 particles is different with the change of Al content in Cu-Al system. When the Al content is above 1.2wt.%, the Al_2O_3 particles tend to distribute along the grain boundaries of copper matrix , whereas when the Al content is above 2.0 wt.%, the Al_2O_3 particles have distributed along the grain boundaries. However, it is interesting to note in Cu-Cr system that most of the formed Cr_2O_3 particles prefer to distribute in the grain of copper matrix when the Cr content is less than 5wt.%, which is quite different from that of Cu-Al system.