Abstract Low cycle fatigue crack initiation was investigated in a Ti-5Al-5Mo-5V-3Cr alloy with a bimodal microstructure. In particular, the crystallographic orientations of both α and β phases at crack initiation sites were characterized. Crack formation is shown to generally proceed along prismatic slip bands in primary α grains. A key role of the interplay between elastic and plastic anisotropies of both α and β phases was evidenced as the crystallographic orientation of the surrounding β matrix is a critical parameter as well. Different lengthscales have thus to be considered for an accurate prediction of fatigue crack initiation in near-β titanium alloys.

中文翻译：

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Ti-5Al-5Mo-5V-3Cr 中低周疲劳裂纹萌生与局部晶体取向的关系

摘要 研究了具有双峰显微组织的Ti-5Al-5Mo-5V-3Cr合金的低周疲劳裂纹萌生。特别是，表征了裂纹萌生位置的 α 和 β 相的晶体取向。裂纹的形成通常沿着初生 α 晶粒中的棱柱滑移带进行。证明了 α 和 β 相的弹性和塑性各向异性之间相互作用的关键作用，因为周围 β 基体的晶体取向也是一个关键参数。因此，为了准确预测近β钛合金中的疲劳裂纹萌生，必须考虑不同的长度尺度。