Strain-controlled fatigue testing of TRIP800 high-strength quenching and partitioning steel

7th Global Conference on Materials Science and Engineering

工业技术（总论）;材料科学

Jiang, Q.Y.^1

School of Mechanical and Electrical Engineering, Changchun Institute of Technology, Changchun

130012, China^1

关键词: Fatigue fracture;    Fracture feature;    Martensite phase transformation;    Quenching and partitioning;    Residual austenite;    Residual compressive stress;    Strain controlled fatigue;    Surface inclusion;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/474/1/012002/pdf
DOI  :  10.1088/1757-899X/474/1/012002

来源: IOP

【 摘 要 】

In this paper, TRIP800 steel plates of thickness of 1.2 mm were subjected to the quenching and partitioning (Q&P) process and underwent strain-controlled fatigue tests. The respective experimental fatigue curves were plotted, and the influencing factors of fatigue resistance were identified and analysed, while the specimen fractographies were examined. The test results show that the existence of residual austenite inhibition of crack extension and strain induced the martensite phase transformation in the residual austenite. The residual compressive stresses improved the fatigue strength of Q&P steel plates under study. The fatigue fracture nucleation occurred in surface inclusions, the crack propagation zone exhibited the ductile fracture mode, while the transient area possessed the brittle fracture features.