ABSTRACT Linear friction welding was used to join Ti–3Al–8V–6Cr–4Mo–4Zr alloy under different pressures, and the microstructure, texture evolution and mechanical properties of the joint were investigated. Results show that the incomplete continuous dynamic recrystallisation (CDRX) occurs during welding, which refines the grains and produces a large number of subgrains in the thermo-mechanically affected zone (TMAZ) and weld centre zone (WCZ). At a higher friction pressure, the width of the WCZ becomes narrower, with the decrease of grain size and the increase of recrystallisation degree. In addition, the texture in the WCZ has changed from {112}<111> to {110}<111>, while the texture in the TMAZ remains at {110}<112>. The tensile properties of the two joints are similar to the base metal (BM), and the microhardness in WCZ and TMAZ are also close to that in BM due to the incomplete CDRX and the decrease of alpha phase.

中文翻译：

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β钛合金的线性摩擦焊接：微观结构演变和力学性能的实验研究

摘要 采用线性摩擦焊在不同压力下连接 Ti-3Al-8V-6Cr-4Mo-4Zr 合金，研究了接头的显微组织、织构演变和力学性能。结果表明，焊接过程中发生不完全连续动态再结晶（CDRX），细化晶粒并在热机械影响区（TMAZ）和焊缝中心区（WCZ）产生大量亚晶粒。在较高的摩擦压力下，WCZ 的宽度变窄，晶粒尺寸减小，再结晶度增加。此外，WCZ 中的纹理已从 {112}<111> 变为 {110}<111>，而 TMAZ 中的纹理保持在 {110}<112>。两个接头的拉伸性能与母材（BM）相似，