固溶温度对冷轧态690合金组织及晶界分布特征的影响  

Effect of solution temperature on microstructure and grain boundary distribution characteristic of cold-rolled 690 alloy

作　　者：王方军 刘璇 刘应龙 吴畏 Wang Fangjun;Liu Xuan;Liu Yinglong;Wu Wei(Chongqing Materials Research Institute Co.,Ltd.,Chongqing 400707,China;National Instrument Functional Materials Engineering,Chongqing 400707,China;Chongqing Key Laboratory of Corrosion-resistant Alloys,Chongqing 400707,China)

机构地区：[1]重庆材料研究院有限公司,重庆400707 [2]国家仪表功能材料工程技术研究中心,重庆400707 [3]耐腐蚀合金重庆市重点实验室,重庆400707

出　　处：《金属热处理》2020年第3期151-157,共7页Heat Treatment of Metals

基　　金：国家科技重大专项(2017ZX06004004);国家重点研发计划(2018YFB2003901);国机集团重大科技专项(INOMAST-ZDZX-2018-05)。

摘　　要：通过SEM和EBSD等手段研究了950~1100℃固溶温度对不同变形量690合金的微观组织和晶界分布特征的影响。结果表明,当固溶温度超过1070℃再结晶晶粒尺寸快速增加,且较大变形量样品的晶粒尺寸小于小变形量的。变形量较小样品的固溶温度相对较大变形量的样品不宜过高。基于晶界的重位点阵(即CSL)理论进一步分析晶界分布特征,固溶处理后进行特征晶界统计分析,样品中由变形加工产生的小角度晶界特征消失,但是具有Σ3晶界特征的退火孪晶组织比例增加。在固溶温度超过1030℃后,Σ3晶界没有明显增加趋势。较大变形量样品的Σ3晶界密度高于低变形量的样品,表明适当提高变形量有利于提高Σ3的晶界密度。对晶粒取向的分布特征统计分析后可知,1030℃固溶处理变形加工后的690合金,提高了Σ3n晶界比例,特别是Σ3晶界,且较大变形量合金形成的Σ3晶界比例为19%,高于小变形量合金的17%比例。Effect of solution temperatures from 950 to 1100℃on microstructure and grain boundary characteristic distribution of 690 alloy with different deformation rate was studied by means of SEM and EBSD.The results show that the grain size of recrystallization increases rapidly when the temperature over 1070℃,and the grain size of the heavier deformed specimens is smaller than that of the slighter deformed specimens.Meanwhile,the solution temperature for the slighter deformed 690 alloy should be lower than that of the heavier deformed specimen.Furthermore,the grain boundary distribution is investigated based on the Coincidence Site Lattice(CSL)theory.After solution treatment,the low angel boundary(LAB)which produced by deformation microstructure is replaced byΣ3 grain boundary with the increase of the number of annealing twins based on the statistic results.The statistic results of grain boundary characteristic distribution show thatΣ3 grain boundary isn’t increased obviously when temperature over 1030℃.In addition,the density ofΣ3 grain boundary of the heavier deformed specimen is higher than that of the slighter specimens.It is indicated that the heavier deformation is positive to the density ofΣ3 grain boundary.From the statistic results of grain orientation,it can be showed that the proportion ofΣ3 nis increased in the deformed 690 alloy after 1030℃solution treatment,especiallyΣ3 grain boundary.At the same time,the amount ofΣ3 grain boundary in the heavier deformed alloy is 19%more than that of the slighter deformed alloy with 17%.

关 键 词：690合金 固溶处理 晶界分布特征 EBSD 

分 类 号：TG156.2[金属学及工艺—热处理]