Effects of Al and Mo on high temperature oxidation behavior of refractory high entropy alloys
Effects of Al and Mo on high temperature oxidation behavior of refractory high entropy alloys
复制标题
Al和Mo对难熔高熵合金高温氧化行为的影响
DOI：
10.1016/s1003-6326(19)65054-5
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发表时间：
2019-07-01
影响因子：
4.5
通讯作者：
Du, Meng
中科院分区：
文献类型：
--
作者：
Cao, Yuan-kui;Liu, Yong;Du, Meng
难熔高熵合金在高温下具有上级力学性能，这类合金的氧化行为非常重要。研究了TiNbTa 0.5Zr、TiNbTa 0.5ZrAl和TiNbTa 0.5ZrAlMo 0.5三种合金的高温氧化行为，并讨论了合金元素的影响。结果表明，TiNbTa0.5Zr和TiNbTa0.5ZrAl合金的氧化速率受扩散控制，且服从指数规律。而TiNbTa 0.5ZrAlMo 0.5合金的氧化速率受界面反应控制，并服从线性规律。Al的添加通过形成保护性氧化皮而导致更好的抗氧化性。但Mo的加入削弱了富铝氧化皮的保护作用。TiNbTa0.5ZrAlMo0.5合金的氧化膜中出现大量的孔隙和裂纹，导致抗氧化性显著降低。
Refractory high entropy alloys have superior mechanical properties at high temperatures, and the oxidation behavior of these alloys is very important. The present work investigated the high temperature oxidation behavior of three alloys with compositions of TiNbTa0.5Zr, TiNbTa0.5ZrAl and TiNbTa0.5ZrAlMo0.5, and the effects of alloying elements were discussed. Results indicated that the oxidation rates of the TiNbTa0.5Zr and TiNbTa0.5ZrAl alloys are controlled by diffusion, and obey the exponential rule. However, the oxidation rate of the TiNbTa0.5ZrAlMo0.5 alloy is controlled by interface reaction, and obeys the linear rule. The addition of Al leads to a better oxidation resistance by forming a protective oxide scale. However, the protection of Al-rich scale is weakened by the addition of Mo. Extensive pores and cracks occur in the oxide scale of the TiNbTa0.5ZrAlMo0.5 alloy, resulting in a significant decrease in oxidation resistance.