缺陷软化效应
(上海交通大学 材料科学与工程学院，上海 200030)
摘 要: 研究了ZrCr2 Laves相金属间化合物的点缺陷结构及其力学性质。 结果表明： 当ZrCr2 Laves相成分偏离化学计量比时， ZrCr2中存在着反位置（组分）缺陷。与其他结构的金属间化合物不同， ZrCr2的显微硬度值在化学计量比处取得最大值， 而断裂韧性则在化学计量比处最小，点缺陷的存在对ZrCr2起着软化作用， 并随着成分偏离化学计量比， ZrCr2的脆性度逐渐降低。 对ZrCr2 Laves相金属化合物中的缺陷结构与其力学性能之间的关系进行了初步讨论。
关键字: 点缺陷；断裂韧性； ZrCr2 Laves相； 金属间化合物
in ZrCr2 Laves-phase compound
（School of Materials Science and Engineering,
Shanghai Jiaotong University， Shanghai 200030, China）
Abstract: The defect structure and mechanical properties in the ZrCr2 Laves-phase compound were studied. The results show that anti-site defects exist in the ZrCr2 Laves phase. A maximum hardness and minimum fracture toughness occur in the stoichiometric composition. The presence of point defects results in softening effect in the ZrCr2 Laves phase, which is contrary to the behavior of most other intermetallic compounds. Meanwhile, the brittleness of the compound decreases when the composition deviates from the stoichiometry. Finally, the relationship between the defect structure and mechanical properties in the ZrCr2 Laves-phase compound was discussed.
Key words: point defect; fracture toughness; ZrCr2 Laves-phase; intermetallic compound
