基于密度泛函理论的第一性原理，通过计算 RuAl 合金氧化物 Al2 O3和 RuO2的氧化能，考察过渡金属元素 X （X ＝W，Mo，、Cr）加入到 RuAl 合金后的占位及对氧化物 Al2 O3和 RuO2的结构稳定性影响。研究表明：经过渡金属元素 X 合金化后，Al2 O3和 RuO2的氧化能均有所增大，增大 Al2 O3氧化能的顺序为：W ＞Mo ＞Cr；增大 RuO2氧化能的顺序为：Mo ＞Cr ＞W，且 RuO2氧化能增大幅度大于 Al2 O3。通过态密度、电荷密度等因素的分析，阐明了 W 对提高 RuAl 抗氧化性能的根本原因是降低了 Al-O 和 Ru-O 的共价键特性，增加了 Al-O 和 Ru-O 的离子键特性；金属元素 X（X ＝W，Mo，Cr）可阻碍 RuAl 金属化合物发生内氧化过程，有利于在 RuAl 表面层的横向方向上形成连续性致密的 Al2 O3氧化层。
Based on the first-principles density functional theory,the placing in the RuAl alloy and the stability effect of the transition metal elements X(X =W,Mo,Cr)on the structure of the oxides Al2 O3 and RuO2 were investigated through the calculation of the oxi-dation energy of the oxides Al2 O3 and RuO2 of RuAl alloy.It is found that the oxidation energy of Al2 O3 and RuO2 is all increased after the alloying of the transition metal X.The sequence of the size increasing for the Al2 O3 oxidation energy is W >Mo >Cr.The sequence of the size increasing for the Al2 O3 oxidation energy is Mo >Cr >W.Among them,the best effect for increasing the anti-oxidation capa-bility to the RuAl alloy is W alloying.Simulfaneously,the analysis of statu’s density and chargy density indicates that the basic reason for W alloying to increase the RuAl anti-oxidation performance is that the co-valent characteristics between the bonds Al-O /Ru-O are reduced,and the ionic band characteristics between the bonds Al-O /Ru-O are increased.Therefore,the alloying of the metal element X can promote the generation of the existing condition for the inner-oxidation process of RuAl metal oxidation,the continuous and dense Al2 O3 oxidation layer is formed on the transverse direction of RuAl surface.
参考文献
| [1] | 李涌泉;谢发勤;吴向清;姚小飞.温度对TiAl合金表面Si-Al-Y共渗层组织结构的影响[J].材料工程,2014(6):22-27. |
| [2] | Shuo Huang;Chuan-Hui Zhang;Rui-Zi Li.Site preference and alloying effect on elastic properties of ternary B2 RuAl-based alloys[J].Intermetallics,2014:24-29. |
| [3] | Bax, B.;Pauly, C.;Leibenguth, P.;Woll, K.;Mücklich, F..Synthesis of B2-RuAl coatings on mild steel by laser cladding[J].Surface & Coatings Technology,201219/20(19/20):3931-3937. |
| [4] | K. B. Povarova;A. E. Morozov;A. A. Drozdov.Development of RuAl-Based Cast Alloys[J].Russian Metallurgy(Metally),20119(9):865-874. |
| [5] | 刘娜;李周;袁华;许文勇;张勇;张国庆.粉末冶金TiAl合金的热变形行为研究[J].航空材料学报,2013(5):1-5. |
| [6] | A. A. Drozdov;A. E. Morozov;K. B. Povarova.Comparative Analysis of the Effect of Mechanical Activation in an Attritor on the Structure and Behavior of p-RuAl and P-NiAl Alloy Powder Mixtures during Reactive Sintering[J].Russian Metallurgy(Metally),20135(5):347-353. |
| [7] | 平发平;胡青苗;杨锐.利用第一原理研究合金化对γ-TiAl抗氧化性能的影响[J].金属学报,2013(4):385-390. |
| [8] | Zhang, J.;Sun, L. Q.;Zhou, Y. C.;Peng, P..Dehydrogenation thermodynamics of magnesium hydride doped with transition metals: Experimental and theoretical studies[J].Computational Materials Science,2015:211-219. |
| [9] | 陈玉勇;崔宁;孔凡涛.变形TiAl合金研究进展[J].航空材料学报,2014(4):112-118. |
| [10] | 张熹雯;朱春雷;李海昭;张继.微量Si改善铸造TiAl合金定向层片组织持久性能研究[J].航空材料学报,2014(1):11-15. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%