INTERNAL OXIDATION BEHAVIOR OF Pd-40Ag-1M (M=Zr, Y) ALLOYS
NING Yuantao;LI Yongnian Kunming Institute of Precious Metals
Cite this article:
NING Yuantao;LI Yongnian Kunming Institute of Precious Metals. INTERNAL OXIDATION BEHAVIOR OF Pd-40Ag-1M (M=Zr, Y) ALLOYS. Acta Metall Sin, 1989, 25(1): 96-103.
Abstract The internal oxidation behavior of Pd-40Ag-1M (M=Zr,Y) alloywires has been studied in air at 800--1200℃. The relationship between the internaloxidation depth ξ and the reaction time t can be expressed as ξ=Kt~n, wheren=0.5--0.75. The higher the temperature is, the larger the n value is the activeelements Zr and Y have different iniernal oxidation characters. For the alloys con-taining Zr, the oxidation rate along the grain boundaries is about twice as thatin grains, and "lateral speed oxidation" exists along the grain boundaries. For thealloys containing Y, the oxidation in grains and along the grain boundaries is rough-ly the same, and do not have "lateral oxidation" along the grain boundaries. Theactivation energies of both alloys are in the range of 120--150 kJ/mol. Some pro-perties of internal oxidized alloys were studied.