(南昌大學(xué) 材料科學(xué)與工程學(xué)院，南昌 330031)
摘 要: 通過透射電鏡和高分辨透射電鏡研究Cu-0.69Cr-0.10Zr-0.02Mg合金在450 ℃早期時(shí)效的析出貫序。研究表明：合金在450 ℃早期時(shí)效的析出貫序?yàn)檫^飽和固溶體→溶質(zhì)偏聚→FCC富Cr的GP區(qū)(Ⅰ)→FCC有序富Cr的GP區(qū)(Ⅱ)→BCC有序富Cr相。在脫溶演變過程中，析出相和基體之間的界面由完全共格界面向共格-半共格界面轉(zhuǎn)變，位向關(guān)系由立方-立方向Nishiyama-Wassermann位向關(guān)系轉(zhuǎn)變。共格界面的形成有利于FCC富Cr相的形成。富Cr析出相的有序化加速析出進(jìn)程，并有利于BCC相的形成，促進(jìn)了Nishiyama-Wassermann位向關(guān)系的發(fā)展。
關(guān)鍵字: Cu-Cr-Zr-Mg合金；析出貫序；時(shí)效；有序化；共格界面；位向關(guān)系
（School of Materials Science and Engineering, Nanchang University, Nanchang 330031, China）
Abstract:The precipitation process in Cu-0.69Cr-0.10Zr-0.02Mg alloy during the early aging stage at 450 ℃ was investigated by transmission electron microscopy and high resolution transmission electron microscopy. The precipitation sequence in the Cu-Cr-Zr-Mg alloy aged at 450 ℃ is supersaturated solid solution → solution segregation → GP zone (Ⅰ) (FCC Cr-rich phase) → GP zone (Ⅱ) (ordered FCC Cr-rich phase) → ordered BCC Cr-rich phase. In the evolution of decomposition, the interface between the precipitates and the Cu matrix changes from the full coherent one to the coherent-partial coherent one, and the orientation relationship changes from the cube-on-cube to Nishiyama-Wassermann. The coherent interface between the FCC Cr-rich precipitates and Cu matrix facilitates the formation of the FCC precipitates. The ordering of Cr-rich precipitates accelerates the precipitation process, which facilitates the formation of the BCC precipitates and promotes the development of Nishiyama-Wassermann orientation relationship.
Key words: Cu-Cr-Zr-Mg alloy; precipitation sequence; aging; ordering; coherent interface; orientation relationship
