基于第一性原理研究Laves相TaCr_2弹性性质和相稳定性  

Study on Elastic Properties and Phase Stability of Laves Phase TaCr_2 by First-principles

作　　者：曾媛[1] 肖璇[1] 贺力[1] 周凯[1] 

机构地区：[1]南昌航空大学航空制造工程学院,江西南昌330063

出　　处：《热加工工艺》2017年第4期54-57,共4页Hot Working Technology

基　　金：国家自然科学基金项目(51161020);江西省自然科学基金项目(20114BAB216012);江西省金属材料微结构调控重点实验室项目(JW201423001)

摘　　要：采用第一性原理方法研究Laves相Ta Cr_2的弹性性质和相稳定性,计算了C15和C14型Laves相Ta Cr_2的弹性性质。结果表明,C15和C14都满足力学性能稳定性的限制条件,且C15比C14更易进行弹性变形;计算了C15和C14型Laves相Ta Cr_2的生成焓与结合能。由计算结果分析可知,C15比C14更易生成,C15比C14稳定;最后计算了C15和C14的电子结构,C15和C14的态密度图均表现出低能成键态和高能反键态区域,但C15的费米能远低于C14,这进一步说明了C15比C14稳定。The elastic properties and phase stability of laves phase TaCr2 were investigated by first-principles method. The elastic properties of C15 and C14 structures were calculated.The results show that C15 and C14 structures both meet the restrictive conditions for the mechanical properties stability. The C15 structure is proner to elastic deformation than C14.Meanwhile, the formation enthalpies and bonding energies of Laves phase C15 and C14 were calculated. From the calculated results, the generation of C15 is easier than C14, and C15 is stabler than C14. Finally, the electronic structures of C15 and C14 are calculated, the density of states of C15 and C14 presents a low-energy well-defined bonding and high-energy anti-bonding region, but the C15＇s Fermi energy is much lower than Cl4.The results furtherly show that C15 is stabler than C14.

关 键 词：第一性原理 Laves相TaCr2 弹性性质 相稳定性 

分 类 号：TG146[一般工业技术—材料科学与工程]