Cyclic Oxidation Kinetics and Thermal Stress Evolution of TiAl Alloys at High Temperature
Shiwei Tian,
Tengkun Zhang,
Shangwu Zeng,
Yefei Zhang,
Dejun Song,
Yulai Chen,
Qiang Kang,
Haitao Jiang
Affiliations
Shiwei Tian
National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Tengkun Zhang
National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Shangwu Zeng
Advisory Planning and Strategic Intelligence Group, China Metallurgical Information and Standardization Institute, Beijing 100730, China
Yefei Zhang
National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Dejun Song
Research Laboratory VIII, Luoyang Ship Material Research Institute, Luoyang 471026, China
Yulai Chen
National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
Qiang Kang
Ansteel Beijing Research Institute Co., Ltd., Beijing 102211, China
Haitao Jiang
National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing, University of Science and Technology Beijing, Beijing 100083, China
The oxidation resistance of TiAl alloys is crucial for their commercial application. In this paper, a cyclic oxidation test with stable air circulation was designed to investigate the cyclic oxidation behavior of the TNM alloy and 4822 alloy at 800 °C and to analyze the phase, morphology, and thermal stress evolution of the oxide layer. The oxidation weight gain curves of both alloys are found to be in parabolic form, and the oxidation reaction orders of the TNM alloy and 4822 alloy are 2.374 and 1.838, respectively. The Nb and Mo elements enhance the antioxidant performance of the TNM alloy by inhibiting the dissolution and diffusion of oxygen, Ti, and Al atoms in the TiAl alloy. The thermal stress evolution of the two alloys during the heating and cooling phases of the cyclic oxidation process are calculated separately, and it is found that the thermal stresses in the TNM alloy are smaller than those in the 4822 alloy, while the maximum thermal stresses appear at the oxide/substrate interface rather than inside the oxide scale, which quantitatively explains the oxidation peeling resistance of the two alloys.
