高熵合金抗高温氧化机理研究展望

近年来高熵合金因具有许多优于传统合金的性能备受瞩目,而高温氧化问题大大限制了其发展应用。多元组成使高熵合金的高温氧化过程不同于单一金属,不同氧化阶段的动力学规律有很大不同。氧化前期多种元素发生氧化反应,氧化物种类和氧化膜结构随时间发生变化,直到稳定氧化阶段氧化产物才固定存在。本文从初期选择性氧化、过渡态氧化和稳定氧化期3个阶段深入剖析高熵合金高温氧化各个过程的详细机理,并总结相应的改善高温抗氧化性能的方法,为高熵合金材料设计和性能调控提供重要的理论依据。

High entropy alloys high temperature oxidation mechanism research prospect

High entropy alloys have been attracting more and more attention in recent years due to performance superior to that of conventional alloys, while the high temperature oxidation limites the application development. Compositionally complex makes the high temperature oxidation process quite different between high entropy alloys and a pure metal. Dynamics of different oxidation periods differ a lot. During the early oxidation stage, several elements undergo oxidation reactions, the spieces of oxide and the structure of scales change with time, and the oxidation products will not become unchanging until the stable oxidation stage. This paper will dissect the detailed mechanism of each oxidation stage during the initial selective oxidation, transition oxidation and stable oxidation, and summarise corresponding approaches to improve antioxidation, hence providing theoretical reference for material design and performance control of high entropy alloys.