Wang Kang, Chen Yuhong, Wang Hongye, et al. Oxidation Behavior of High Entropy Mo25Nb25Ta25W25 Alloy[J]. Special Casting & Nonferrous Alloys, 2018,38(6):661-665.
Wang Kang, Chen Yuhong, Wang Hongye, et al. Oxidation Behavior of High Entropy Mo25Nb25Ta25W25 Alloy[J]. Special Casting & Nonferrous Alloys, 2018,38(6):661-665. DOI: 10.15980/j.tzzz.2018.06.023.
高熵合金Mo25Nb25Ta25W25的氧化行为
摘要
探究氧化物层的破裂和钼的氧化物挥发在高熵合金Mo
25
Nb
25
Ta
25
W
25
的氧化动力学中的作用机理。通过热压烧结制备了具有简单BCC结构的Mo
25
Nb
25
Ta
25
W
25
高熵合金。分别研究其在800、900和1 000℃下的氧化动力学行为
并对其氧化机理进行了初步描述。通过XRD、SEM和电子探针对氧化物进行表征。结果表明
在整个氧化温度范围内
氧化层中主要氧化产物为Ta
16
W
18
O
94
和Nb
14
W
3
O
47
具有一定的保护性。试样在800℃下遵循抛物线规律
随试验温度升高
生成的MoO
3
挥发
氧化层变得疏松多孔
使合金在900℃的中期和1 000℃开始满足直线规律。
Abstract
The action mechanism of oxide layer crack and volatilization of molybdenum oxides in the oxidative kinetics of high entropy alloy Mo
25
Nb
25
Ta
25
W
25
was described.An equal mole ratio Mo
25
Nb
25
Ta
25
W
25
alloy with a simple BCC structure was prepared by hot-pressing sintering.The oxidation behavior of the high entorpy alloy were analyzed at 800℃、900℃and 1 000℃
respectively
and the oxidation mechanism was expounded.The oxides were characterized by XRD
SEM and electron probe X-ray microanalyzer(EPMA).The results reveal that at oxidation temperature range
the main oxidation products are Ta
16
W
18
O
94
and Nb
14
W
3
O
47
with some protection in the oxide layer.The kinetics of the tested samples follows the parabolic law at 800℃
while follows the linear law at the middle of 900℃and1 000℃
which are attributed to the volatilization of MoO
3
leading to oxide layer loose and porous at higher temperature.
关键词
高熵合金高温抗氧化氧化动力学氧化机理
Keywords
High Entropy AlloyHigh Temperature Oxidation ResistanceOxidation KineticsOxidation Mechanism