The effect of annealing on the microstructures and oxidation behaviors of AlCoCrFeNi complex concentrated alloys
The effect of annealing on the microstructures and oxidation behaviors of AlCoCrFeNi complex concentrated alloys
复制标题
退火对AlCoCrFeNi复合浓合金显微组织和氧化行为的影响
DOI：
10.1016/j.jallcom.2023.170391
复制
发表时间：
2023
影响因子：
6.2
通讯作者：
Weaver, Mark L.
中科院分区：
文献类型：
--
作者：
Butler, Todd M.;Pavel, Michael J.;Weaver, Mark L.
本文报道了1050℃惰性气氛下退火对Alx(CoCrFeNi)1−xCCAs （x = 8、12、15、20和30 (at%)）复合浓缩合金显微组织和高温氧化行为的影响。在所有情况下，退火稳定了由BCC， B2和/或FCC相组成的多相显微组织，最终相组成取决于合金中的Al含量。所有合金都表现出短暂的瞬态氧化，然后是不同程度的抛物线式氧化生长。铸态合金的抗氧化能力随着Al含量的增加而提高，主要是cr2o3的形成。退火后，所有合金都转变为Al2O3形成体，但质量增加高达20%。将实验结果与合金相平衡和氧化产物的热力学模型进行比较，结果表明，退火后合金表面附近富Al相的体积分数增加，为Al2O3的形成提供了Al储层，从而提高了抗氧化性。结合现有的M-Cr-Al氧化模型，讨论了氧化机理。
This paper reports the effects of annealing at 1050 °C in an inert atmosphere on the microstructures and high temperature oxidation behaviors of Alx(CoCrFeNi)1−xCCAs, where x = 8, 12, 15, 20, and 30 (at%) complex concentrated alloys. In all cases, annealing stabilized multi-phase microstructures consisting of a combination of BCC, B2, and/or FCC phases with the final phase constitution being dependent on the Al content in the alloy. All the alloys exhibited brief periods of transient oxidation, followed by various degrees of parabolic oxide growth. The as-cast alloys, which were observed to predominantly be Cr2O3formers, oxidation resistance increased with increasing Al content. After annealing, all of the alloys transitioned into Al2O3formers but with increased mass gain up to 20 at% Al. Comparison of the experimental results with thermodynamic models of alloy phase equilibria and oxidation products suggests that an increase in the volume fractions of Al-rich phases near the alloy surfaces as a result of annealing, increases oxidation resistance by providing Al reservoirs for the formation of Al2O3. The oxidation mechanisms are discussed relative to existing M-Cr-Al oxide formation models.