Tribo-corrosion response of additively manufactured high-entropy alloy
Tribo-corrosion response of additively manufactured high-entropy alloy
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DOI：
10.1038/s41529-021-00177-2
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发表时间：
2021-06
影响因子：
5.1
通讯作者：
J. Shittu;Maryam Sadeghilaridjani;M. Pole;Saideep Muskeri;Jie Ren;Yanfang Liu;Ismael Tahoun
中科院分区：
文献类型：
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作者：
J. Shittu;Maryam Sadeghilaridjani;M. Pole;Saideep Muskeri;Jie Ren;Yanfang Liu;Ismael Tahoun
具有多个主元素的高熵合金（HEAs）代表了结构合金设计的范式转变，并在腐蚀环境中显示出优异的表面抗降解性。在这里，激光工程网状CoCrFeMnNi HEA的摩擦腐蚀响应进行了评价，在3.5重量%的NaCl溶液中，在室温下。增材制造（AM版）CoCrFeMnNi在摩擦腐蚀测试期间显示出比电弧熔化对应物低五倍的磨损率、再生钝化和更高的腐蚀电位。与沿着构建方向和垂直于构建方向的测试相比，在与构建方向成45°的摩擦腐蚀响应中观察到显著的各向异性，显示出更好的性能。开路电位曲线的特征在于随着磨损开始急剧下降至更负的值，然后是活性摩擦力的连续变化，腐蚀持续时间，并最终在测试结束时跳到更高的值，表明AM合金具有优异的表面再钝化。AM处理的CoCrFeMnNi的上级耐摩擦腐蚀性归因于在增材制造期间形成的亚晶粒胞状结构促进的细化的显微组织和高度保护性的表面钝化层。这些结果突出了在极端环境中使用HEAs的增材制造的潜力，这些极端环境需要耐摩擦腐蚀性，机械耐用性，延长使用寿命和具有低尺寸公差的净成形的组合。
High-entropy alloys (HEAs) with multiple principal elements represent a paradigm shift in structural alloy design and show excellent surface degradation resistance in corrosive environment. Here, the tribo-corrosion response of laser-engineered net-shaped CoCrFeMnNi HEA was evaluated in 3.5 wt% NaCl solution at room temperature. The additively manufactured (AM-ed) CoCrFeMnNi showed five times lower wear rate, regenerative passivation, and nobler corrosion potential during tribo-corrosion test compared to its arc-melted counterpart. A significant anisotropy was seen in the tribo-corrosion response with 45° to the build direction showing better performance compared to tests along the build direction and perpendicular to it. The open circuit potential curves were characterized by a sharp drop to more negative values as wear began, followed by continuous change for the active tribo-corrosion duration and finally a jump to nobler value at the end of the test indicating excellent surface re-passivation for the AM-ed alloy. The superior tribo-corrosion resistance of AM-ed CoCrFeMnNi was attributed to the refined microstructure and highly protective surface passivation layer promoted by the sub-grain cellular structure formed during additive manufacturing. These results highlight the potential of utilizing additive manufacturing of HEAs for use in extreme environments that require a combination of tribo-corrosion resistance, mechanical durability, extended service life, and net shaping with low dimensional tolerance.