Additively manufactured titanium metal matrix composites (TMCs) reinforced with TiB₂ ceramic particles and prepared using selective laser melting (SLM) were subjected to annealing at 850 °C for 2 h. The effect of annealing on the microstructures was characterized through a scanning electron microscope (SEM) and electron backscatter diffraction (EBSD). The martensitic structure of plain Ti–6Al–4 V changed to a lamellar structure after annealing. An increase in the weight percentage of a TiB₂ powder induced a drastic change in the overall morphology. A considerable refinement of both α and β grains enabled β grains to obtain a globular shape. The change in the microstructure can be attributed to the pinning effect caused by the formation of TiB precipitates and the β phase. Wear performance is enhanced with an increase in the weight percentage of TiB. The tribological performance confirmed that the growth of β grains acts as an obstacle to plastic deformations, and delamination improved with the help of TiB in the matrix.

Graphical abstract

中文翻译：

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SLM 退火 Ti64 等轴 α/β 微观结构的演变：TiB2 的作用

增材制造的钛金属基复合材料 (TMC) 用 TiB ₂陶瓷颗粒增强并使用选择性激光熔化 (SLM) 制备，在 850 °C 下退火 2 小时。通过扫描电子显微镜 (SEM) 和电子背散射衍射 (EBSD) 表征退火对微观结构的影响。退火后，纯 Ti-6Al-4 V 的马氏体结构变为层状结构。_{TiB 2}的重量百分比增加粉末引起整体形态的剧烈变化。α 和 β 晶粒的显着细化使 β 晶粒获得球形。微观结构的变化可归因于由 TiB 析出物和 β 相的形成引起的钉扎效应。随着 TiB 重量百分比的增加，磨损性能得到增强。摩擦性能证实 β 晶粒的生长阻碍了塑性变形，并且在基体中的 TiB 的帮助下分层得到改善。

图形概要