基于高通量场发射扫描电镜建立的高温合金γ’相定量统计表征方法  

A Quantitative and Statistical Method of γ' Precipitates in Superalloy Based on the High-Throughput Field Emission Scanning Eelectron Microscope

作　　者：卢毓华 王海舟[1,2] 李冬玲 付锐[3] 李福林 石慧[1,2] LU Yuhua;WANG Haizhou;LI Dongling;FU Rui;LI Fulin;SHI Hui(Beijing Advanced Innovation Center for Materials Genome Engineering,Central Iron and Steel Research Institute,Beijing 100081,China;Beijing Key Laboratory of Metal Materials Characterization,NCS Testing Technology Co.,Ltd.,Beijing 100081,China;High Temperature Material Research Institute,Center Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]钢铁研究总院北京材料基因工程高精尖创新中心,北京100081 [2]钢研纳克检测技术股份有限公司金属材料表征北京市重点实验室,北京100081 [3]钢铁研究总院高温材料研究所,北京100081

出　　处：《金属学报》2023年第7期841-854,共14页Acta Metallurgica Sinica

基　　金：国家重点研发计划项目No.2016YFB0701401。

摘　　要：以5种不同固溶冷却速率制备的新型变形GH4096高温合金作为研究对象,基于高通量场发射扫描电镜(SEM)的高速采集和原位可视化的优点,研究合金中的一次、二次和三次γ’相定量表征分析方法。研究过程包括,利用MIPAR软件建立了分割和识别流程,实现合金中一次、二次和三次γ’相的准确识别。通过57000倍和3000倍SEM像中一次γ’相面积分数比值、二次和三次γ’相数量比值、二次和三次γ’相面积分数等随图像张数的变化,得到了能获取γ’相定量统计数据的最小视场:13×13张2048×2048像素尺寸的57000倍图像的表征区域。通过建立方法获取到γ’相定量数据,且数据趋势与标准化的小角X射线散射(SAXS)法结果一致。结合冷却速率的快慢对本方法获取的γ’相定量数据以及图像形貌进行讨论,实验结果与经典的形核和长大机制及Ostwald Ripening机制的理论结果相符。不同冷却速率样品的400℃拉伸强度不同,但与γ’相定量结果存在相关性:强度高的样品,冷速相对较快,二次γ’相数量较多,γ’相面积分数总和也较高。本工作得到的GH4096高温合金的γ’相定量统计结果对于探讨GH4096高温合金的工艺优化和性能预测具有参考意义。Superalloys are used widely in national defense,energy,maritime,aviation,and other vital areas requiring stable and reliable materials owing to their excellent oxidation and heat corrosion resistance,high-temperature strength,good fatigue performance,and fracture toughness.The presence of a coherent gamma prime(γ') precipitate is the main factor affecting the high-temperature mechanical properties.Therefore,obtaining the quantitative and statistical γ' precipitate data is indispensable for examining and developing new superalloys.On the other hand,conventional instruments and methods barely achieve this goal.In this study,high-throughput field emission scanning electron microscope(highthroughput SEM) was introduced because of its high-speed imaging and original position visualization.Based on the high-throughput SEM,an innovative deformation GH4096 superalloy prepared at five different solution cooling rates were used as an object to establish a quantitative and statistical method for characterizing the primary,secondary,and tertiary γ' precipitates.Many images of γ' precipitates with magnifications of ×57000 and ×3000 were obtained rapidly,and methodologies for recognizing the γ' precipitates were developed using MIPAR software.Matrices of images of different amounts were formed.Through these methodologies,information on these matrices was obtained,including the ratio of the primary γ' precipitates area fractions between images with magnifications of ×57000 and ×3000.The ratio between the amounts of secondary and tertiary γ' precipitates and the area fraction of the secondary and tertiary γ' precipitates varied with the number of images investigated,respectively.By comparing the tendencies of these three results,the minimum field of view that could represent the actual distribution of γ'precipitates was set to a matrix of 13 × 13 images with a magnification of ×57000 and a pixels square of 2048 × 2048.Considering the consistency between the results of the standardized small-angle X-ray scattering

关 键 词：GH4096高温合金 纳米级颗粒 γ’相 高通量场发射扫描电镜 图像分析 表征区域 

分 类 号：TG146.1[一般工业技术—材料科学与工程]