GH4169合金中富铌相的定量统计分布表征方法研究及应用  

Study on quantitative statistical distribution characterization method for niobium-rich phase in GH4169 alloy and its application

作　　者：宋妍 王蓬 杨植岗 周晴晴 李冬玲 鲍磊 SONG Yan;WANG Peng;YANG Zhigang;ZHOU Qingqing;LI Dongling;BAO Lei(Central Iron and Steel Research Institute Co.,Ltd.,Beijing 100081,China;Beijing Key Laboratory of Metallic Materials Characterization,Beijing 100081,China;NCS Testing Technology Co.,Ltd.,Beijing 100081,China)

机构地区：[1]钢铁研究总院有限公司,北京100081 [2]金属材料表征北京市重点实验室,北京100081 [3]钢研纳克检测技术股份有限公司,北京100081

出　　处：《冶金分析》2024年第4期1-8,共8页Metallurgical Analysis

基　　金：国家重点研发计划(2021YFB3702103,2022YFF0609301)。

摘　　要：GH4169合金中加入了大量的铌元素来提高其高温强度,在其制备过程中不可避免产生铌偏析,并导致较多富铌相的产生,这些富铌相的形貌、数量、尺寸及其分布均会对材料的力学性能产生直接影响,因此有必要对富铌相进行原位定量统计分布表征。本文基于扫描电子显微镜(SEM)多视场自动采集和能谱高效分析技术,建立了GH4169合金大尺寸范围内全域微米级富铌相的定量统计分布表征方法,通过对扫描电子显微镜亮度、对比度进行设置,能谱计数采集时间的优化,实现了富铌相颗粒与基体组织图像的良好分割和微米级富铌相的可靠检出,获得了测试区域内全域富铌相的位置、形貌、尺寸、数量等信息,并绘制了富铌相二维分布图和尺寸频度分布图谱。将方法应用于GH4169合金棒材横截面不同区域富铌相的定量统计分布表征,探讨了棒材中心到边缘富铌相数量、尺寸分布的演变规律。富铌相数量呈中心、边缘少,r/2(r为半径)处多的趋势;富铌相中心平均尺寸最大,r/2与边缘富铌相平均尺寸较为接近,较中心处有减小趋势。对后续改进工艺,降低富铌相的尺寸提供了参考。A large amount of niobium is added into GH4169 alloy to improve the high temperature strength.Niobium segregation is inevitably generated during the preparation process,leading to the formation of many niobium-rich phases.The morphology,quantity,size and distribution of these niobium-rich phases will have a direct impact on the mechanical properties of the material,so it is necessary to conduct the quantitative original position statistical distribution characterization of niobium-rich phases.In this paper,a quantitative statistical distribution characterization method for the full range of micron niobium-rich phases in GH4169 alloy was established based on scanning electron microscope(SEM)multi-field automatic acquisition and energy spectrum efficient analysis technology.By setting the brightness and contrast of scanning electron microscope and optimizing the acquisition time of energy spectrum counting,the good segmentation of niobium-rich particles and matrix images as well as reliable detection of micron-grade niobium-rich phases were achieved.The information of the full range of micron niobium-rich phases in the test area,including the position,morphology,size and quantity,was obtained.Moreover,the two-dimensional distribution diagrams and size frequency distribution diagrams of the niobium-rich phase were drawn.The proposed method was applied to the quantitative and statistical distribution characterization of niobium-rich phases in different areas of cross sections of GH4169 alloy bars.The evolution law of quantity and size distribution of niobium-rich phases from center to edge of bars was discussed.The quantity of niobium-rich phases showed the trend of less at center and edge but more at r/2(r was the radius)position.The average size of niobium-rich phases at center was maximum.The average size was similar at r/2 position and edge,but it decreased at the center.This study provided reference for the subsequent improvement process to reduce the size of niobium-rich phases.

关 键 词：富铌相 扫描电子显微镜(SEM) 能谱(EDS) 定量统计分布 GH4169合金 尺寸 数量 

分 类 号：TF649[冶金工程—钢铁冶金] TG115.215[金属学及工艺—物理冶金]