High-Temperature Oxidation Behavior of Refractory High-Entropy Alloys: Effect of Alloy Composition
High-Temperature Oxidation Behavior of Refractory High-Entropy Alloys: Effect of Alloy Composition
复制标题
DOI：
10.1007/s11085-016-9696-y
复制
发表时间：
2017-10-01
影响因子：
2.2
通讯作者：
Heilmaier, Martin
中科院分区：
文献类型：
--
作者：
Gorr, Bronislava;Mueller, Franz;Heilmaier, Martin
研究了W-Mo-Cr-Ti-Al、Nb-Mo-Cr-Ti-Al和Ta-Mo-Cr-Ti-Al等摩尔组成的新型高熵耐火合金(HEAs)在1000℃和1100℃下的高温氧化行为。基于这些等摩尔起始成分，本研究的主要目的是选择最有希望的合金体系，使其性能得到连续改善。尽管Ta-Mo-Cr-Ti-Al的难熔元素含量较高，但在1000和1100A℃下仍表现出良好的抗氧化性能。含W和Nb的HEA具有中等的增重值和复杂的氧化动力学。这些合金形成了不均匀的氧化膜，由于形成了不连续的富铬和富铝氧化膜，形成了具有厚层和多孔层的区域，以及显示出非常薄的氧化膜的区域。Ta-Mo-Cr-Ti-Al合金表现出最有希望的行为，由于形成了薄而致密的富铝层，其氧化物的生长遵循抛物线规律。
The high-temperature oxidation behavior of a new family of refractory high-entropy alloys (HEAs) with compositions of W-Mo-Cr-Ti-Al, Nb-Mo-Cr-Ti-Al and Ta-Mo-Cr-Ti-Al was studied at 1000 and 1100 A degrees C. Based on these equimolar starting compositions, the main incentive of this study was to select the most promising alloy system whose properties may then be successively improved. Despite the high amount of refractory elements, Ta-Mo-Cr-Ti-Al showed good oxidation resistance at 1000 and 1100 A degrees C. Moderate values of mass gain and complex oxidation kinetics were observed for the W- and Nb-containing HEAs. These alloys formed inhomogeneous oxide scales possessing regions with thick and porous layers as well as areas revealing quite thin oxide scales due to the formation of discontinuous Cr- and Al-rich scales. The most promising behavior was shown by the alloy Ta-Mo-Cr-Ti-Al which followed the parabolic rate law for oxide growth due to the formation of a thin and compact Al-rich layer.