First-principles investigation of the composition dependent properties of Ni(2+x)Mn(1-x)Ga shape-memory alloys
文献类型：期刊论文
| 作者 | C. M. Li ; H. B. Luo ; Q. M. Hu ; R. Yang ; B. Johansson ; L. Vitos |
| 刊名 | Physical Review B
 |
| 出版日期 | 2010 |
| 卷号 | 82期号:2 |
| 关键词 | ni-mn-ga exchange interactions ferromagnetic metals phase-transformation electronic-structure martensitic phase potential model ni2mnga approximation temperatures |
| ISSN号 | 1098-0121 |
| 中文摘要 | The composition dependent lattice parameter, phase stability, elastic moduli, and magnetic transition temperature of the Ni(2+x)Mn(1-x)Ga shape-memory alloys are studied by using the first-principles exact muffin-tin orbital method in combination with the coherent potential approximation. The lattice parameter and tetragonal shear modulus of the cubic L(21) austenite phase decreases linearly with increasing concentration x of excess Ni atoms. The heats of formation of both cubic L(21) and tetragonal beta''' phases and their difference increase with x, indicating decreasing stability of the cubic and tetragonal phases and increasing driving force for the L(21) to beta''' martensitic transition. Investigating the electronic density of states, we find that the Ni-induced decreasing phase stability can mainly be ascribed to the weakening of the covalent bonding between minority spin states of Ni and Ga. Using the computed parameters, the composition dependence of the martensitic transition temperature is discussed. The theoretical Curie temperature, estimated from the Heisenberg model in combination with the mean-field approximation, is larger for the beta''' phase than for the L(21) phase. For both phases, the Curie temperature decreases nearly linearly with increasing x. |
| 原文出处 | |
| 公开日期 | 2012-04-13 |
| 源URL | [http://ir.imr.ac.cn/handle/321006/31204]  |
| 专题 | 金属研究所_中国科学院金属研究所 |
| 推荐引用方式 GB/T 7714 | C. M. Li,H. B. Luo,Q. M. Hu,et al. First-principles investigation of the composition dependent properties of Ni(2+x)Mn(1-x)Ga shape-memory alloys[J]. Physical Review B,2010,82(2). |
| APA | C. M. Li,H. B. Luo,Q. M. Hu,R. Yang,B. Johansson,&L. Vitos.(2010).First-principles investigation of the composition dependent properties of Ni(2+x)Mn(1-x)Ga shape-memory alloys.Physical Review B,82(2). |
| MLA | C. M. Li,et al."First-principles investigation of the composition dependent properties of Ni(2+x)Mn(1-x)Ga shape-memory alloys".Physical Review B 82.2(2010). |
入库方式： OAI收割
来源：金属研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。