GH4099合金轧棒内部条带粗晶形成机理  

Formation mechanism on band-type coarse grain structure in GH4099 alloy rolled bar

作　　者：王楷萌 刘华松 夏长林 裴丙红 闫智然 郭啸东 王杨 WANG Kaimeng;LIU Huasong;XIA Changlin;PEI Binghong;YAN Zhiran;GUO Xiaodong;WANG Yang(Branch of Vanadium and Titanium Research Institute,Ansteel Beijing Research Institute Co.,Ltd.,Beijing 102200,China;Science and Technology Quality Department,Pangang Group Jiangyou Changcheng Special Steel Co.,Ltd.,Jiangyou 621704,China)

机构地区：[1]鞍钢集团北京研究院有限公司钒钛研究院分院,北京102200 [2]攀钢集团江油长城特殊钢有限公司科技质量部,江油621704

出　　处：《中国有色金属学报》2025年第4期1167-1178,共12页The Chinese Journal of Nonferrous Metals

摘　　要：GH4099合金轧棒热处理后出现内部条带粗晶,导致其高温持久性能波动。本文系统研究不同固溶时间下条带粗晶的形貌特征、演变规律、碳化物分布形态及局部微区元素分布,结合热力学计算揭示其形成机理。结果表明:条带粗晶的形成与Mo、Ti和Cr元素的负偏析密切相关。上述元素的条带状负偏析降低了晶界碳化物的析出量,碳化物熟化过程进一步弱化晶界钉扎作用,引发局部晶粒异常长大。随着固溶时间延长,晶粒沿低钉扎力方向优先生长,最终形成条带粗晶。The GH4099 alloy rolled bars exhibit internally band-type coarse grain structure after heat treatment,leading to unstable high-temperature stress rupture properties.This study systematically investigated the features and evolution of the band-type coarse grains under different time of solution heat treatment,and carbides morphology,as well as local elements distributions.The formation mechanisms on the band-type coarse grains were further revealed through thermodynamic calculations.The results indicate that the formation of band-type coarse grains is closely related to the negative segregation of Mo,Ti,and Cr elements.The banded negative segregations of these elements reduce the precipitation amount of carbides on the grain boundaries,while the coarsening process of carbides further weakens the grain boundary pinning effect,triggering abnormal grain growth of local grains.As the solution treatment time increases,grains preferentially grow along the direction of lower pinning force,eventually forming the band-type coarse grains.

关 键 词：高温合金 GH4099 条带粗晶 元素偏析 

分 类 号：TG146.1[一般工业技术—材料科学与工程]