Silicon (Si) and reactive elements (REs) like hafnium (Hf) have favorable effects on improving the high-temperature oxidation resistance. To reveal the interaction effect between them, Si with different contents was a...Silicon (Si) and reactive elements (REs) like hafnium (Hf) have favorable effects on improving the high-temperature oxidation resistance. To reveal the interaction effect between them, Si with different contents was added into P-NiAlHf alloy in this study. Cyclic oxidation behavior at 1200℃ was investigated. Results show that Si can increase the Hf-rich precipitates and suppress Hf outward diffusion, thus inhibit the RE effect leading to worse oxidation resistance. However, NiAlHf-5Si alloy exhibited a lower oxidation rate and better spallation resistance mainly because of the existence of micro-cracks and Ni2 Al3 phases which provided more rapid diffusion paths for Al^3+.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 51425102)the China Postdoctoral Science Foundation (Nos. 2017T100023 and 2016M600028)
文摘Silicon (Si) and reactive elements (REs) like hafnium (Hf) have favorable effects on improving the high-temperature oxidation resistance. To reveal the interaction effect between them, Si with different contents was added into P-NiAlHf alloy in this study. Cyclic oxidation behavior at 1200℃ was investigated. Results show that Si can increase the Hf-rich precipitates and suppress Hf outward diffusion, thus inhibit the RE effect leading to worse oxidation resistance. However, NiAlHf-5Si alloy exhibited a lower oxidation rate and better spallation resistance mainly because of the existence of micro-cracks and Ni2 Al3 phases which provided more rapid diffusion paths for Al^3+.
