Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : October 07, 2017 - October 09, 2017
Failure analysis of hydrogen compressor (hydrogen pressure : 20 MPa, number of cycles to failure : 6.1×106 cycles) was conducted. Chemical composition analysis, Microstructure observation, tensile test and Vickers hardness measurement showed that the material used was SCM440H which was sound. SEM observation of fracture surface showed that the connection part of hydrogen compressor was fatigue-failured. The maximum stress σmax = 573 MPa of cyclic loading was estimated from fracture toughness KIC = 199 MPa・m1/2 for SCM435. It was inferred from the maximum stress σmax = 573 MPa and S-N diagram (stress ratio R = 0) of SCM440 that the connection part was fatigue failured at the number of cycles to failure Nf = 6.1×106 cycles.
