690合金中晶界网络分布的控制及其对晶间腐蚀性能的影响  

Controlling the Grain Boundary Network to Enhance the Intergranular Corrosion Resistance in Alloy 690

作　　者：李慧[1] 夏爽[1] 周邦新[1] 陈文觉[1] 刘廷光[1] 胡长亮[1] 

机构地区：[1]上海大学材料研究所,上海200072

出　　处：《中国材料进展》2011年第5期11-14,33,共5页Materials China

基　　金：科技部973计划项目(2011CB610502;2006CB605001);国家自然科学基金资助项目(50974148);上海市科委项目(09DZ1100103);上海大学创新基金项目

摘　　要：利用形变及热处理工艺提高了690合金的低Σ重位点阵(Coinc idence S ite Lattice,CSL)晶界比例,通过电子背散射衍射(EBSD)技术表征了由不同类型晶界构成的网络特征,结果表明通过晶界工程处理,能够形成以大尺寸"互有Σ3n取向关系晶粒的团簇"显微组织为特征的晶界网络分布,这种显微组织是再结晶过程中多重孪晶充分发展的结果。通过晶间腐蚀浸泡实验表明通过晶界工程处理的样品抗晶间腐蚀性能较未经过晶界工程处理的样品明显提高。腐蚀后样品的显微形貌表明大尺寸"互有Σ3n取向关系晶粒的团簇"能够阻止晶间腐蚀向样品内部扩展,并且能够保护下层的显微组织。The proportion of low E coincidence site lattice （CSL） grain boundaries was enhanced by grain boundary en- gineering （GBE） in Alloy 690. The grain boundary network was characterized by electron backscatter diffraction （EBSD） technique. Formation of large size grain-cluster is the feature of the grain boundary network after GBE treatment. All of the grains in this kind of cluster had E3~ mutual misorientations regardless of whether they were adjacent. This microstructure is the result of multiple twinning during recrystallization. The resistance to intergranular corrosion was greatly enhanced by GBE. By observing the morphology of the corroded specimens, it was found that the large size grains-cluster microstructure reduced the penetration of the intergranular corrosion, and protected the inner microstructure.

关 键 词：690合金 晶界工程 晶间腐蚀 多重孪晶 

分 类 号：TG349[金属学及工艺—金属压力加工]