Short Fatigue Crack Initiation and Propagation in Ti-6A1-4V with Short-bar and Lamellar Microstructures

摘要：

Long-focus microscopy and scanning electron microscopy (SEM) were used to investigate short fatigue crack initiation and propagation in Ti-6A1-4V alloy with two kinds of microstructures:short-bar and lamellar. Short crack (SC) growth rates in the two microstructures were measured and compared with long crack at three load ratios. For the lamellar microstructure,SC initiation and propagation are strongly affected by slip band and grain boundary, however they exhibit less microstructure-sensitivity for short-bar microstructure. SC propagates with higher da/ dN than long cracks at the same △K in both microstructures, but only in the lamellar microstructure SC can propagate below the long crack threshold △Kth,. Finally crack-microstructure interactions and crack closure level are discussed to explain the anomalous crack growth rates.

关键词： Short fatigue crack Crack-microstructure interaction Crack growth rate Ti-6Al-4V

作者: Yingjie Ma Jiafeng Lei Jianrong Liu Yuyin Liu Rui Yang

作者单位: Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China

会议类型: 国际会议

会议名称: The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)

会议地点: 北京

会议语种:英文

页码: 1312-1316

在线出版日期: 2011-06-19（万方平台首次上网日期，不代表论文的发表时间）