全片层组织TiAl-Nb合金屈服强度的价键理论计算  

Yield Strength Calculation of Fully Lamellar TiAl-Nb Alloys with Valence-Bond Theory

作　　者：刘伟东[1] 屈华[1] 周宇[1] 刘志林[1] 

机构地区：[1]辽宁工学院,辽宁锦州121001

出　　处：《稀有金属材料与工程》2006年第6期855-859,共5页Rare Metal Materials and Engineering

基　　金：辽宁省教育厅项目(05L185;202163348);辽宁省自然科学基金项目(20031083)联合资助

摘　　要：在TiAl基合金相空间与相界面价电子结构计算的基础上,利用表征相结构单元成键能力的相结构因子F与表征界面结合强度的界面结合因子?ρ给出了一种计算TiAl基合金屈服强度的方法。该方法以实验数据为基础,进行回归分析求α2相体积分数,以理论屈服强度与实际屈服强度之差是否满足一级近似作为合金基体γ相强度σsγ-TiAl取值的判据,用相结构单元最强键上的共用电子对数nA计算Nb在γ相与α2相中的含量WγNb和WαN2b。计算了全片层TiAl,TiAl-8Nb,TiAl-10Nb合金的屈服强度,与实测值比较,理论计算结果令人满意。The yield strengths of TiAl-based alloys were calculated with the factors of phase structure F and interface binding Δρ based on the calculation of their phase space and interface structures. The factor F and factor Δρ represent the bonding power of the phase structure units and the bond strength of the interface, respectively. The volume fraction α2 of the phase was analyzed on the base of the experimental findings. The value of σs^γ-TiAl which represents the strength of the matrix phase γ of TiAl-based alloys, is determined by whether the difference of the theoretical and actual yield strengths accorded with the first approximation. The Wγ^Nb and Wα2^Nb, which represent the contents of the element Nb in the phase γ, and α2, respectively, were calculated with the nA, the share electron pairs in the strongest bond in the structure unit. The yield strengths of the fully lamellar alloys TiAl, TiAl-8Nb, TiAl-10Nb were calculated and compared with the measured values. It is found that the values of theoretical calculation are satisfied..

关 键 词：TiAl-Nb合金 价电子结构 屈服强度 计算 

分 类 号：TG111[金属学及工艺—物理冶金]