Experimental Investigation on Fatigue Crack Propagation Behavior of Nuclear Pipe at High Temperature

In order to study the fatigue crack growth performance of nuclear piping materials at elevated temperature above 500℃, the fatigue crack propagation rate experiments on the materials of base metal, welded seam and heat affected zone of tube were carried out under high temperature conditions. The probabilistic fatigue crack growth curves with different survival rates were obtained according to the method of probability analysis. The results show that there are obvious differences in fatigue crack growth performance of materials in different positions of pipelines at high temperature, and the resistance of fatigue crack propagation for welded seam and heat-affected zone is much better than that of base metal. The results can be used for safety assessment and fracture mechanics analysis of nuclear reactor pipeline structure.