缺陷軟化效應(yīng)
(上海交通大學(xué) 材料科學(xué)與工程學(xué)院，上海 200030)
摘 要: 研究了ZrCr2 Laves相金屬間化合物的點(diǎn)缺陷結(jié)構(gòu)及其力學(xué)性質(zhì)。 結(jié)果表明： 當(dāng)ZrCr2 Laves相成分偏離化學(xué)計(jì)量比時(shí)， ZrCr2中存在著反位置（組分）缺陷。與其他結(jié)構(gòu)的金屬間化合物不同， ZrCr2的顯微硬度值在化學(xué)計(jì)量比處取得最大值， 而斷裂韌性則在化學(xué)計(jì)量比處最小，點(diǎn)缺陷的存在對ZrCr2起著軟化作用， 并隨著成分偏離化學(xué)計(jì)量比， ZrCr2的脆性度逐漸降低。 對ZrCr2 Laves相金屬化合物中的缺陷結(jié)構(gòu)與其力學(xué)性能之間的關(guān)系進(jìn)行了初步討論。
關(guān)鍵字: 點(diǎn)缺陷；斷裂韌性； ZrCr2 Laves相； 金屬間化合物
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
