对疲劳裂纹萌生寿命和扩展速率的研究表明，４０Ｃｒ钢调质和正大态存在加载频率效应，而１Ｃｒ１８Ｎｉ９Ｔｉ钢固溶处理态未发现加载频率效应。引起加载频率效应的实质是，随加载频率不断提高，金属材料塑性变形传播速度不断减小，从而改变塑性区特性，在塑性区诸多的影响因素中，塑性应变幅度的减小和残余压应力的提高，对延迟疲劳裂纹萌生和减慢裂纹扩展速率起主导作用。
Studies of the fatigue crack initiation and propagation show that there is the loading frequency effect for the quenched and tempered or normalized 40Cr steel, but no the loading frequency effect for the solution treated ICr18Ni9Ti. The essential reason that causes the loading frequency effect is due to decrease in the plastic deformation propagation speed with the inereasing loading frequency. The decrease in plastic strain amplitude and the increase in residual compressive stress play a main role for the delaying fatigue crack initiation and the retarding crack propagation. The study of the loading frequency effect on the fatigue behaviour of the metals with the lower plastic deformation propagation speed possesses important engineering signification. Correspondent: FENG Zhongxin, associate professor, Institute of Metallic Materials and Strength, Xi'an Jiaotong University, Xi'an 710049
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | 冯忠信,张建中,杨建军,陈新增．金属学报,1995 |
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