【摘要】 采用磁悬浮熔炼法制备了固溶体合金Ti Mox(x=0.03、0.13、0.25、0.50、1.00,x为Mo与Ti原子数之比),经活化后与H-D混合气(D原子占50%)反应,反应平衡后用质谱分析气相中H和D的含量。根据反应前气相中H和D的含量,由质量守恒定律求得固相中H和D的含量。根据气、固两相中的氕氘原子数之比(D/H),由公式α(H-D)=([D]/[H])(固相)/([D]/[H])(气相)计算得到H-D分离因子α(H-D)。结果表明:20℃下,x为0.03~1.00时,α(H-D)>1.00,合金氢化物表现为正同位素效应。随着Mo含量的增加,α(H-D)由1.04增加到1.27;x>0.50时,α(H-D)基本保持不变。x=0.03时α(H-D)≈1.00,合金表现为零同位素效应。根据以前热分析实验结果,Ti Mo0.03吸氢后析出大量负同位素效应的Ti H2,并有少量正同位素效应的Ti-Mo合金氢化物,零同位素效应是两者共同作用的结果。根据Mo含量和分离因子的关系,室温下H原子倾向于占据4Ti四面体间隙位置,而D原子倾向于占据能量较高的3Ti1 Mo四面体间隙位置。更多还原

【Abstract】 The alloys with various Mo content TiMox(x=0.03,0.13,0.25,0.50,1.00,atomic ratio) were prepared with electromagnetic levitation technique.The alloys after activation reacted rapidly with H-D gas mixture(D%=50%),the composition of the mixture in equilibrium of isotope exchange was determined using a mass-spectroscopy.H-D separation factor α(H-D) was defined as()s/()g,in which s refers to the atomic ratio of D and H in solid phase,and g refers to the atomic ratio of D and H in gas phase.The results showed that at 20 ℃,x=0.03-1.00,α(H-D) >1.00,D prefered to stay at solid phase,and the preference becomed stronger as the Mo content increases,with α(H-D) rising from 1.04 to 1.27.α(H-D) kept nearly unvaried when x=0.50-1.00.α(H-D)≈1.00 when x=0.03,namely TiMo0.03 hydride showed zero effect,through previous TG-DSC analysis results,the hydride contains TiH2 with negative effect,and Ti-Mo hydrides with positive effect,so it is the total effect of the two hydrides with oppositive effect.From the relationship between the Mo content and α(H-D),H atom prefers to take 4Ti tetrahedral interstice,whereas D atom tends to take 3Ti1Mo position in which the energy level is higher than that of 4Ti position.更多还原