(上海交通大學 材料科學與工程學院, 上海 200030)
摘 要: 采用綴加平面波加局域軌道方法和廣義梯度近似對立方C15結(jié)構(gòu)的ZrCr2 Laves相金屬間化合物的彈性性質(zhì)， 包括彈性常數(shù)和彈性模量， 以及層錯能進行理論計算。 結(jié)果表明： 計算得到的ZrCr2 Laves相的彈性性質(zhì)與實驗結(jié)果相近， 其泊松比和彈性各向異性系數(shù)大小說明ZrCr2 中原子鍵合的方向性并不強烈； ZrCr2 Laves相的內(nèi)稟和外稟層錯能分別為112 mJ/m2和98 mJ/m2。 并計算了層錯與位錯的彈性交互作用。 對ZrCr2 Laves相的力學特性和變形機制進行了討論。
關鍵字: 彈性常數(shù)； 彈性模量； 堆垛層錯能; ZrCr2 Laves 相； 第一性原理
（School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200030, China）
Abstract: First-principles calculations were performed to investigate the elastic constants, elastic moduli, stacking fault energies, and dislocation dissociations of C15 ZrCr2 Laves phase, based on the method of augmented plane waves plus local orbitals with generalized gradient approximation. The results show that the calculated elastic properties are close to the experimental results. The high value of Poisson's ratio and low value of elastic anisotropy ratio imply that the interatomic force in ZrCr2 is weakly directional. The intrinsic and extrinsic stacking fault energies of ZrCr2 Laves phase are found to be 112 mJ/m2 and 98 mJ/m2, respectively, and the elastic interactions between faults and dislocations are considered. Finally, the mechanical properties and deformation mechanism of ZrCr2 Laves phase are discussed with the calculated results.
Key words: elastic constant; elastic modulus; stacking fault energy; ZrCr2 Laves phase; First-principles
