THE EFFECTS OF STORED ENERGY AND RECRYSTALLIZATION ON THE CREEP RUPTURE PROPERTIES OF INTERNALLY OXIDIZED COPPER-ALUMINA AND COPPER-SILICA ALLOYS

摘要

Copper-silica and copper-alumina alloys of low oxide content were produced by the internal oxidation and extrusion of copper-silicon and copper-aluminum alloy powders. These alloys show normal behavior after recrystallization. With increasing amounts of recrystallization at temperatures up to 1050℃, the creep rupture strength at 450℃ decreases and the ductility increases. Cold work of the partially or completely recrystallized alloys results in an increase in creep rupture strength and a decrease in ductility.nThe strength of dispersed oxide hardened alloys of this kind is due to a combination of micron or sub-micron dispersion of an insoluble oxide and a high value of stored energy through cold work. In the as-extruded condition, both the dispersion and the cold work impede the dislocation movements. After recrystallization the only impediment to dislocation movement is the oxide dispersion. Improved ductility and higher creep rates are a result.