Approaching "stainless magnesium" by Ca micro-alloying
Approaching "stainless magnesium" by Ca micro-alloying
复制标题
DOI：
10.1039/d0mh01380c
复制
发表时间：
2021-02-01
影响因子：
13.3
通讯作者：
Zheludkevich, Mikhail L.
中科院分区：
文献类型：
--
作者：
Deng, Min;Wang, Linqian;Zheludkevich, Mikhail L.
镁及镁合金的严重腐蚀是阻碍其在交通运输业、医疗植入物和水溶液电池中广泛应用的主要问题。以前，没有发现镁基材料的腐蚀速率明显低于超高纯镁，即在浓NaCl溶液中的0.25 mm y（-1）。在这项工作中，首次发现高耐蚀性的镁可以通过钙微合金化来溶解，使“不锈镁”更接近。所设计的Mg-Ca贫合金具有令人难以置信的低腐蚀速率，在3.5wt % NaCl溶液中小于0.1mm y（-1），这显著低于超高纯Mg和迄今为止报道的所有Mg合金。钙微合金化抑制了阴极水还原动力学、稳定了杂质和形成了保护性表面膜，从而使合金具有优异的耐蚀性。结合环境友好性和经济可行性，钙微合金化为开发具有不同应用的先进镁基材料提供了巨大的可行性。
Severe corrosion of Mg and Mg alloys is a major issue hindering their wider application in transportation industry, medical implants and aqueous batteries. Previously, no Mg-based material has been found with a significantly lower corrosion rate than that of ultra-high-purity Mg, i.e. 0.25 mm y(-1) in concentrated NaCl solution. In this work for the first time, highly corrosion-resistant Mg is found to be accomplishable by Ca micro-alloying, bringing "stainless Mg" closer. The designed Mg-Ca lean alloys possess incredibly low corrosion rates, less than 0.1 mm y(-1) in 3.5 wt% NaCl solution, which are significantly lower than that of ultra-high-purity Mg and all Mg alloys reported thus far. The outstanding corrosion resistance is attributed to inhibition of cathodic water reduction kinetics, impurities stabilizing and a protective surface film induced by Ca micro-alloying. Combined with the environmental benignity and economic viability, Ca micro-alloying renders huge feasibility on developing advanced Mg-based materials for diverse applications.