【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.更多还原

【Abstract】 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.更多还原