Steady-State Creep Behavior of Super304H Austenitic Steel at Elevated Temperatures  

作　　者：Ping Ou Long Li Xing-Fei Xie Jian Sun 

机构地区：[1]Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming,School of Materials Science and Engineering,Shanghai Jiaotong University [2]School of Materials Science and Engineering,Jiangxi University of Science and Technology

出　　处：《Acta Metallurgica Sinica(English Letters)》2015年第11期1336-1343,共8页金属学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.50931003);the Shanghai Science and Technology Committee(No.13dz2260300)

摘　　要：Creep behavior of Super304H austenitic steel has been investigated at elevated temperatures of 923-973 K and at applied stress of 190-210 MPa. The results show that the apparent stress exponent and activation energy in the creep deformation range from 16.2 to 27.4 and from 602.1 to 769.3 kJ/mol at different temperatures, respectively. These high values imply the presence of a threshold stress due to an interaction between the dislocations and Cu-rich precipitates during creep deformation. The creep mechanism is associated with the dislocation climbing governed by the matrix lattice diffusion. The origin of the threshold stress is mainly attributed to the coherency strain induced in the matrix by Cu-rich precipitates. The theoretically estimated threshold stresses from Cu-rich precipitates agree reasonably with the experi- mental results.Creep behavior of Super304H austenitic steel has been investigated at elevated temperatures of 923-973 K and at applied stress of 190-210 MPa. The results show that the apparent stress exponent and activation energy in the creep deformation range from 16.2 to 27.4 and from 602.1 to 769.3 kJ/mol at different temperatures, respectively. These high values imply the presence of a threshold stress due to an interaction between the dislocations and Cu-rich precipitates during creep deformation. The creep mechanism is associated with the dislocation climbing governed by the matrix lattice diffusion. The origin of the threshold stress is mainly attributed to the coherency strain induced in the matrix by Cu-rich precipitates. The theoretically estimated threshold stresses from Cu-rich precipitates agree reasonably with the experi- mental results.

关 键 词：Super304H steel Cu-rich precipitate CREEP Threshold stress 

分 类 号：TG142.1[一般工业技术—材料科学与工程]