Abstract

AlCoCrCuFeNi high entropy alloy particles were laser surface alloyed on Ti–6Al–4V substrate to improve the tribological properties. The microstructure, phase formation and hardness improvement of the laser alloyed surface were examined. The wear resistance of the laser alloyed specimen were evaluated through pin-on-disc apparatus and compared with substrate specimen. The wear mechanism of the worn-out surface and roughness were studied. The laser alloyed specimen exhibits dual solid solution along with the BCC phase. The alloyed region shows dendrite and interdendrite structure with equiaxed grain formation. The hardness of laser alloyed region is 3 times higher than the substrate material due to dominant BCC phase formation. The laser alloyed specimen shows higher wear resistance compared to substrate due to solid solution strengthening and intermetallic formation. The wear resistance of the laser alloyed specimen was 2.62 times than the substrate at 50 N load and 0.9 m/s sliding velocity. Abrasive, adhesive wear and severe plastic deformation were observed in the substrate specimen, whereas in the laser alloyed specimen mild abrasive wear was observed. The laser alloyed specimen has 0.56 times the coefficient of friction of the Ti–6Al–4V substrate at 50 N load and 0.9 m/s sliding velocity due to self-lubrication property of HEA elements. Surface roughness of worn-out laser alloyed specimen was 0.44 times that of the Ti–6Al–4V substrate.

Graphic Abstract

中文翻译：

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通过激光表面合金化在Ti–6Al–4V上的AlCoCrCuFeNi高熵合金的组织演变和磨损行为

摘要

在Ti-6Al-4V衬底上对AlCoCrCuFeNi高熵合金颗粒进行了激光表面合金化处理，以改善其摩擦学性能。研究了激光合金化表面的微观结构，相形成和硬度提高。激光合金化试样的耐磨性通过销钉盘设备进行评估，并与基底试样进行比较。研究了磨损表面的磨损机理和粗糙度。激光合金化的试样与BCC相一起显示出双重固溶体。合金化区域显示出具有等轴晶形成的枝晶和枝晶结构。由于主要的BCC相形成，激光合金化区域的硬度比基底材料高3倍。由于固溶强化和金属间化合物的形成，与基材相比，激光合金化的样品具有更高的耐磨性。在50 N负载和0.9 m / s的滑动速度下，激光合金化试样的耐磨性是基材的2.62倍。在基材样品中观察到磨料，粘合剂磨损和严重的塑性变形，而在激光合金化样品中观察到了轻微的磨料磨损。由于HEA元件的自润滑特性，在50 N负载下，激光合金化试样的Ti-6Al-4V基底的摩擦系数为0.56倍，滑动速度为0.9 m / s。磨损的激光合金化试样的表面粗糙度是Ti-6Al-4V基板的0.44倍。9 m / s的滑动速度。在基材样品中观察到磨料，粘合剂磨损和严重的塑性变形，而在激光合金化样品中观察到了轻微的磨料磨损。由于HEA元件的自润滑特性，在50 N负载下，激光合金化试样的Ti-6Al-4V基底的摩擦系数为0.56倍，滑动速度为0.9 m / s。磨损的激光合金化试样的表面粗糙度是Ti-6Al-4V基板的0.44倍。9 m / s的滑动速度。在基材样品中观察到磨料，粘合剂磨损和严重的塑性变形，而在激光合金化样品中观察到了轻微的磨料磨损。由于HEA元件的自润滑特性，在50 N负载下，激光合金化试样的Ti-6Al-4V基底的摩擦系数为0.56倍，滑动速度为0.9 m / s。磨损的激光合金化试样的表面粗糙度是Ti-6Al-4V基板的0.44倍。

图形摘要