| Abstract Scope |
The high temperature mechanical response of nanocrystalline Cu-Ta alloys have been the recent focus of several fundamental studies. Such studies have included the high temperature creep response, high dose radiation damage immunity, high thermal conductivity and prolonged (10,000s hrs) high temperature stability. Despite the extraordinary property-set, stable passivating oxides have not been developed within the family of Cu-Ta alloys, prohibiting them in applications such as next generation heat exchangers. Here we report engineering the environmental degradation behavior of the new oxidation resistant Cu-Ta-Cr alloys, for the first time. Studies were carried out using constant heating and isothermal gravimetric experiments up to 1000C. The microstructural changes, and nature of the oxides were analyzed using x-ray diffraction, scanning electron microscopy, and transmission electron microscopy. In the most extreme case a stable protective oxide layer, which otherwise didn’t exist in the binary case at any temperature, was maintained to above 700C. |