Nb和Ta对TiAl晶体中H扩散性能的计算研究  

Calculation study on diffusion properties of H in TiAl crystal with Nb and Ta

作　　者：陆英[1] 张超彦[1,2] LU Ying;ZHANG Chaoyan(Xuzhou College of Industrial Technology,Xuzhou 221100,CHina;North University of China,Taiyuan 030051,China)

机构地区：[1]徐州工业职业技术学院,江苏徐州221100 [2]中北大学,山西太原030051

出　　处：《兵器材料科学与工程》2021年第6期71-75,共5页Ordnance Material Science and Engineering

基　　金：江苏省社科基金(2018SJA1031);江苏高校“青蓝工程”资助。

摘　　要：采用第一性原理研究Nb和Ta对TiAl晶体中H扩散性能的影响。结果表明:在纯TiAl晶体中,H原子倾向于占据富Ti的八面体间隙,通过相邻四面体间隙时扩散势垒更低,倾向于Ti层内扩散;Nb和Ta均倾向于置换Ti生成置换固溶体,Nb和Ta固溶均导致H在TiAl晶体中的扩散系数降低,且随温度升高,对扩散系数的降低效果更强,其中Ta作用更强。The effects of Nb and Ta elements on the diffusion of H in TiAl crystals were investigated by first principles method.The results show that in pure TiAl crystal,H atom tends to occupy the octahedral gap rich in Ti,and the diffusion barrier become lower when passing through the adjacent tetrahedral gap. Nb and Ta elements both tend to displace Ti site to form substitutional solid solution. Both Nb and Ta solution can reduce the diffusion coefficient of H in TiAl crystal,and the effect is stronger with the increase of temperature,Ta has a more obvious effect.

关 键 词：Nb和Ta TIAL 扩散 第一性 

分 类 号：TG146.2[一般工业技术—材料科学与工程]