The development of alloys with high antioxidation performance is limited by the ambiguous details of the oxidation mechanism.Here,based on the structures of internal oxides detected by high-resolution transmission ele...The development of alloys with high antioxidation performance is limited by the ambiguous details of the oxidation mechanism.Here,based on the structures of internal oxides detected by high-resolution transmission electron microscopy,a hybrid method combining first-principles calculation,climb image nudged elastic band method and quasi-harmonic Debye model has been implemented to explain the oxidation mechanism with an emphasis on the origin of delamination and cracking.The results showed that the delamination of oxides corresponds to the acceleration of diffusion of Cr element caused by lamellar structures.The reduction in the cracking occurrence at high temperature mainly results from the smaller bulk modulus of oxides.Furthermore,the stronger chemical bonds promoted by lamellar structures also correspond to the higher crackingresistance.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12174296,U20A20279,U1532268,U1932134 and U1867215)the Key Research and Development Program of Hubei Province(Grant No.2021BAA057)+2 种基金Hubei Provincial Colleges and Universities Excellent Young and Middle-aged Science and Technology Innovation Team Project(Grant No.T201903)Wuhan City Applied Basic Frontier Project(Grant No.2019010701011382)Wuhan University of Science and Technology Graduate Innovation and Entrepreneurship Fund(Grant No.JCX2021094)and 111 Project(Grant No.2018018)。
文摘The development of alloys with high antioxidation performance is limited by the ambiguous details of the oxidation mechanism.Here,based on the structures of internal oxides detected by high-resolution transmission electron microscopy,a hybrid method combining first-principles calculation,climb image nudged elastic band method and quasi-harmonic Debye model has been implemented to explain the oxidation mechanism with an emphasis on the origin of delamination and cracking.The results showed that the delamination of oxides corresponds to the acceleration of diffusion of Cr element caused by lamellar structures.The reduction in the cracking occurrence at high temperature mainly results from the smaller bulk modulus of oxides.Furthermore,the stronger chemical bonds promoted by lamellar structures also correspond to the higher crackingresistance.
