In this study, we investigated stress corrosion cracking (SCC) behaviors in a near alpha titanium alloy (Ti-6Al-3Nb-2Zr-1Mo) with distinct microstructures and microtextures. By analyzing fracture surfaces, crack growth paths, and grain orientations, we found that the SCC crack growth rate increased with an increase in the volume fraction of the primary α phase, due to elevated crack initiation density and concentrated grain orientations. Additionally, SCC cracks exhibited a preference for propagating along boundaries between neighboring soft macrozones (easy for slip) and hard macrozones (relatively hard for slip), as well as through macrozones favorable for slip.

中文翻译：

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显微组织和宏观区域对近α钛合金应力腐蚀开裂敏感性的影响

在这项研究中，我们研究了具有独特微观结构和微观纹理的近 α 钛合金 (Ti-6Al-3Nb-2Zr-1Mo) 的应力腐蚀开裂 (SCC) 行为。通过分析断裂面、裂纹扩展路径和晶粒取向，我们发现，由于裂纹萌生密度增加和晶粒取向集中，SCC裂纹扩展速率随着初生α相体积分数的增加而增加。此外，SCC 裂纹倾向于沿着相邻的软宏观区域（易于滑动）和硬宏观区域（相对难以滑动）之间的边界扩展，以及穿过有利于滑动的宏观区域。