摘要
为了研究氢对钛晶体弹性模量的影响,采用基于密度泛函理论的第一原理赝势平面波方法对α-Ti、β-Ti、不同钛-氢原子比的α-Ti-H和β-Ti-H晶体模型进行了完全几何优化,计算了优化后晶体的弹性模量,通过差分电荷密度分析了氢影响钛晶体弹性模量的作用机理.计算得到的Ti/H原子比为16∶1的α-Ti-H晶体的弹性模量小于α-Ti晶体,而Ti/H原子比为8∶1的α-Ti-H晶体的弹性模量大于α-Ti晶体.不同Ti/H原子比的β-Ti-H晶体的弹性模量均大于β-Ti晶体.研究表明,氢降低了低氢含量的α-Ti-H晶体的弹性模量,提高了β-Ti-H晶体的弹性模量.
In order to study the effect of hydrogen on the elastic moduli of titanium crystals, the crystal structure models of α - Ti, β - Ti, as well as α - Ti - H and β - Ti - H with different Ti/H atom ratios were fully optimized firstly, and then the elastic moduli of optimized crystals were calculated by using the first-principles method based on plane-wave pseudopotential and density function. The mechanism of effect of hydrogen on the elastic moduli of titanium crystals was analyzed using charge density difference. The calculated elastic moduli of α -Ti -H crystals with Ti/H atom ratios of 16：1 and 8：1 are lower and higher than those of α -Ti crystal, respectively ; the calculated elastic moluli of β - Ti - H crystals with different Ti/H atom ratios are all higher than those of β - Ti crystal. The results indicate that the interstitial H atom can reduce the elastic moduli of α - Ti - H crystal with low hydrogen content and increase the elastic moduli of β - Ti - H crystals.
出处
《材料科学与工艺》
EI
CAS
CSCD
北大核心
2009年第3期305-310,共6页
Materials Science and Technology
基金
国家自然科学基金资助项目(50671028)
关键词
钛晶体
氢
第一原理
晶体结构
弹性模量
Ti crystal
hydrogen
first-principles
crystal structure
elastic moduli
