核反应堆压力容器模拟钢中纳米富Cu相的变形特征  

Deformation Characterization of Nano-Scale Cu-Rich Precipitates in Reactor Pressure Vessel Model Steel

作　　者：蔡琳玲[1,2] 徐刚[1,2] 冯柳[1,2] 王均安[1,2] 彭剑超[1,2] 周邦新[1,2] 

机构地区：[1]上海大学材料研究所,上海200072 [2]上海大学微结构重点实验室,上海200444

出　　处：《上海大学学报（自然科学版）》2012年第3期311-316,共6页Journal of Shanghai University:Natural Science Edition

基　　金：国家重点基础研究发展计划(973计划)资助项目(2011CB610503);国家自然科学基金重点资助项目(50931003);上海市重点学科建设资助项目(S30107)

摘　　要：提高了Cu含量的核反应堆压力容器(reactor pressure vessel,RPV)模拟钢样品,经过880 cC水淬、660℃调质处理和400℃1000～4000 h的等温时效处理,观察到纳米富Cu相的析出;随后进行20%～30%冷轧变形,采用萃取复型(extractionreplica,ER)和高分辨透射电镜(high resolution transmission electron microscopy,HRTEM)的方法研究纳米富Cu相的变形特征.研究结果表明,镶嵌在α-Fe基体中的纳米富Cu相,在冷轧变形时的变形机制较为复杂,存在多种变形方式.当纳米富Cu相的晶体处于有利取向时,可以跟随基体一起发生滑移变形,表现为"软"颗粒的特性;当晶体处于不利取向时,会发生孪生变形,甚至诱发马氏体相变,有时生成"轮毂辐条"状的孪晶结构,大大提高了纳米富Cu相继续变形时的抗力,表现为"硬"颗粒的特征,因而析出纳米富Cu相会产生明显的强化作用.The nano-scale Cu-rich precipitates in reactor pressure vessel （RPV） model steel after water quenching, tempering and thermal aging at 400℃has been investigated by extraction replica （ER） and high resolution transmission electron microscopy （HRTEM）. Samples were cold-rolled by 20% -30% after aging to study the deformation characterization of Cu-rich precipitates. The results show that the deformation characterization of the nanometer Cu-rich precipitates is complicated due to the restriction of α-Fe matrix. Different deformation mechanisms are detected. When the Cu-rieh precipitates are located in a favorable orientation, they will be deformed by slipping together with the deformation of α-Fe matrix to show the particles of ＂soft＂ characteristic. When the Cu-rich precipitates are located in an unfavorable orientation, they will be deformed by twinning to form the spoke-like twins within a Cu-rich precipitate, even a martensitic phase transformation induced by strain. In this case, the Cu-rich precipitates show the particles of ＂hard＂ characteristic. Therefore the precipitation hardening occurs after the formation of Cu- rich precipitates in α-Fe matrix.

关 键 词：核反应堆压力容器模拟钢 富Cu相 变形 萃取复型 高分辨透射电镜 

分 类 号：TG113[金属学及工艺—物理冶金]