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用板状缺口试样研究了在自约束条件下，表面增碳和渗氮对3Cr2W8V钢冷—热疲劳裂纹萌生、扩展及裂纹形态特征的影响。结果表明，表面增碳及渗氮均使钢的热疲劳裂纹萌生及扩展抗力降低，渗氮尤为显著。经渗氮处理的试样在冷—热疲劳试验中除缺口尖端出现主裂纹外，试样表面较早出现大量裂纹，最后形成龟裂；表面增碳的试样在试验中也出现少量表面裂纹，而表面化学成分无变化的试样则未出现表面裂纹。
The effects of surface carburization and nitriding on the initiation and propagation of cold-thermal fatigue crack initiation and propagation and crack morphology in 3Cr2W8V steel under self-restrained conditions were studied by means of plate-notched specimens. The results show that both surface carbonization and nitriding reduce the thermal fatigue crack initiation and propagation resistance of steel, especially for nitriding. In the cold-thermal fatigue test, except for the main crack at the notch tip, the nitrided sample appeared a large number of cracks early and finally formed a crack. The surface carbon-enhanced sample also appeared a small amount of surface cracks in the test , While no changes in the surface chemical composition of the sample is no surface cracks.