摘要
用三点弯曲试样测定了不同方法冶炼的轴承钢疲劳裂纹的扩展规律,研究了微观组织参数和晶界偏析对裂纹扩展的影响。结果表明晶粒和碳化物大小及晶界化学性质是疲劳裂纹扩展的主要控制因素。此外,运用位错偶极子理论讨论了轴承钢疲劳裂纹的扩展机理。
The behavior of fatigue crack propagation in stee1 GCr_(15) supplied throughdifferent metallurgical processes wa8 investigated with three--point bending(TPB) specimens used, and the effect of microstructural parameters and grainboundary segregation on the crack propagation discussed as well. The resultsshow that the sizes of grains and carbides and the chemical properties of grainboundary are the dominant factors to control fatigue crack propagation. Also,the mechanism of fatigue crack propagation in bearing steel is discussed onthe basis of dislocation dipole theory.
关键词
轴承
钢
疲劳
裂纹
扩展机理
fatigue
microstructural parameter
grain boundary segregation
dislocation dipole
