热处理过程中690合金热轧棒材显微组织演变  

Microstructure evolution during heat treatment in hot-rolled alloy 690

作　　者：郝宪朝[1] 熊超[1] 梁田[1] 陈波[1] 高明[1] 刘奎[1] 夏亮 

机构地区：[1]中国科学院金属研究所,辽宁沈阳110016 [2]中国中原对外工程有限公司,北京100191

出　　处：《材料热处理学报》2017年第1期112-117,共6页Transactions of Materials and Heat Treatment

摘　　要：采用不同热处理工艺对热轧态690合金棒材进行处理,研究了合金的晶粒长大倾向,分析了晶粒尺寸对碳化物析出及晶界区域化学成分演变的影响。结果表明:690合金晶粒尺寸均随着固溶温度升高而增大。TT处理对合金晶粒尺寸的影响不明显。晶粒尺寸较大的690合金晶界碳化物较为连续,碳化物粗大、间距小、呈细条状,晶内含有少量的颗粒状碳化物;细小晶粒的合金晶界碳化物尺寸细小、间距大、呈颗粒状,晶粒内碳化物数量增加。随碳化物沿晶界析出,晶界区域Cr、Ni和Fe含量发生变化。与大晶粒尺寸的合金相比,小晶粒的690合金晶界最低Cr浓度增加,贫Cr区宽度明显减小。Alloy 690 heat-treated by different processes was employed to study the grain growth behavior and the effect of grain size variation on intergranular carbide precipitation and composition of grain boundaries.The results show that the grain growth tendency increases with the increasing solid solution treating temperature,but the aging time has little effect on the grain growth.After thermal treatment（ aging）,carbides are precipitated at grain boundaries.Intergranular carbides are more continuous and coarse and of strip morphology in the samples with bigger grain size,while the carbides are small,dispersal in the small grain samples.Cr-depleted zone occurs and the Cr,Ni and Fe concentration changes at the grain boundaries.The minimum Cr concentration is higher and the width of Crdepleted zones is smaller in the samples with small grains than that in the samples with big grains.

关 键 词：690合金 固溶处理 TT处理 晶粒 

分 类 号：TG132.33[一般工业技术—材料科学与工程]