Activation Energy of Oxidation of Novel Co-Al-W Superalloys at High Temperatures

作者：Xu Yangtao^*; Xia Tiandong; Zhao Wenjun; Wang Xiaojun; Yan Jianqiang

来源：Rare Metal Materials and Engineering, 2011, 40(4): 701-704.

• Co-Al-W superalloy
• high-temperature oxidation
• activation energy
• alloying elements

Co-Al-W alloy is a novel Co-base superalloy, with the precipitation strengthening phase of ternary compound gamma'-Co(3)(Al,W). The kinetic data of oxidation mass gain were measured for the Co-Al-W alloy at 800 and 900 degrees C in air, and the oxidation rate constants at different temperatures were determined by the relevant linear fitting. According to Arrhenius relation of the oxidation rate constants, the activation energy of oxidation was derived for this alloy at 800 and 900 degrees C. It is found that 9W alloy has the highest value of activation energy of oxidation among 7.5W, 9W and 10.7W at different temperatures. The addition of refractory elements Mo, Nb, Ta and Ti can change the mass gain and activation energy of oxidation of the Co-Al-W alloy; therefore, the oxidation resistance of the superalloy at high temperatures can be forecast.

• 出版日期2011-4
• 单位兰州理工大学