Mechanical Mechanism of Nucleation of Creep Void in P91 Heat Resistant Steel
The mechanical behavior of creep void nucleation in P91 heat-resistant steel was investigated using experimental combined with crystal plasticity finite element method.The distribution of misorientation between grains around creep voids was observed.A crystal plasticity finite element model was constructed and the effects of grain misorientation(8.4°,16.9°,33.6°,50°,65.8° and 77.1°)on the stresses at grain boundary were calculated.The results showed that the stresses at grain boundary decreased gradually with time during creep,and the location of the maximum stress changed due to grain rotation and the activation of slip system.The stress concentration intensity was high when the grain misorientation angles were in ranges of 33.6°～50.0°.It indicated that the grain misorientation affected the stress at grain boundary,so that the nucleation of creep void was contributed in the grain misorientation,which was supported by EBSD observations.
万方数据
维普
