Liu Chengsong, Liu Daoxin, Zhang Xiaohua, Yu Shouming, Zhao Weidong
Corrosion and Protection Research Laboratory, Northwestern Polytechnical University, 127 You Yi Xi Road, Xi'an 710072, China.
Materials (Basel). 2017 Jul 20;10(7):833. doi: 10.3390/ma10070833.
The effect of the ultrasonic surface rolling process (USRP) on the rotary bending fretting fatigue (FF) of Ti-6Al-4V alloy was investigated. The reason for the USRP's ability to improve the FF resistance of Ti-6Al-4V alloy was studied. The results revealed that the USRP induced a compressive residual stress field with a depth of 530 μm and a maximum residual stress of -930 MPa. Moreover, the surface micro-hardness of the USRP sample was significantly higher than that of the untreated base material (BM) sample, and the USRP yielded a 72.7% increase in the FF limit of the alloy. These further enhanced fatigue properties contributed mainly to the compressive residual stress field with large numerical value and deep distribution, which could effectively suppress FF crack initiation and early propagation. The USRP-induced surface work-hardening had only a minor impact on the FF resistance.
研究了超声表面滚压工艺（USRP）对Ti-6Al-4V合金旋转弯曲微动疲劳（FF）的影响。研究了USRP提高Ti-6Al-4V合金抗FF能力的原因。结果表明，USRP诱导出深度为530μm、最大残余应力为-930MPa的压缩残余应力场。此外，USRP样品的表面显微硬度明显高于未处理的基体材料（BM）样品，USRP使合金的FF极限提高了72.7%。这些进一步增强的疲劳性能主要归因于数值大且分布深的压缩残余应力场，它可以有效地抑制FF裂纹的萌生和早期扩展。USRP诱导的表面加工硬化对FF抗性的影响较小。
