第三代单晶高温合金WZ30的凝固组织研究  

Study on solidification microstructure of a third generation single crystal superalloy WZ30

作　　者：赵运兴 马德新 魏剑辉 员莹莹 徐维台 李侣 邓阳丕 ZHAO Yunxing;MA Dexin;WEI Jianhui;YUAN Yingying;XU Weitai;LI Lü;DENG Yangpi(Powder Metallurgy Research Institute,Central South University,Changsha 410083,China;Wedge Central South Research Institute Co.Ltd.,Shenzhen 518045,China;Wedge Aviation Technology Co.Ltd.,Shenzhen 516466,China)

机构地区：[1]中南大学粉末冶金研究院,湖南长沙410083 [2]深圳市万泽中南研究院有限公司,广东深圳518045 [3]深圳市万泽航空科技有限责任公司,广东深圳516466

出　　处：《中南大学学报(自然科学版)》2025年第2期478-486,共9页Journal of Central South University:Science and Technology

基　　金：深圳市科技计划项目(JSGG20220831092800001);广东省引进创新创业团队项目(607264877417)。

摘　　要：采用螺旋选晶法制备国产第三代单晶高温合金WZ30的单晶试棒,对其铸态组织进行研究,利用电子探针分析铸件中的元素偏析,测算WZ30单晶铸件中各合金元素的分凝系数,并与第二代单晶合金CMSX-4进行对比。研究结果表明:WZ30合金铸件中出现了更为严重的雀斑形成倾向和更多的γ/γ′共晶组织。经EBSD检测,γ/γ′共晶团与γ基体的晶体取向保持一致,说明枝晶间的共晶组织是在γ基体上形核并长大的。枝晶臂中的元素分布并不是连续渐变,而是存在台阶式的突变,表明在凝固过程中,枝晶臂的长大是分阶段进行的。由于合金中添加了更多的高偏析难熔元素Re,大部分合金元素的偏析更为严重,从而导致铸态组织中雀斑形成倾向和共晶含量的增加。The single crystal(SC)bars of the third-generation SC superalloy WZ30 were prepared by spiral grain selector method.The as-cast microstructure was examined.The element segregation in castings was analyzed by scanning electron probe(EPMA)across a dendritic arm.The segregation coefficients of various alloying elements in WZ30 castings were evaluated and compared with that of the second-generation alloy CMSX-4.The results show that in alloy WZ30 the freckling extent becomes more pronounced and the eutectic fraction is significantly higher than that in alloy CMSX-4.According to EBSD detection result,the crystal orientation ofγ/γ'eutectic islands is consistent with that ofγmatrix,indicating that the eutectic nucleates on theγdendrite as matrix.The distribution of elements in the dendrite arms is not a continuous gradient,but a stepped abrupt variation,indicating that the growth of dendrite arms during solidification is carried out in stages.Due to the more addition of refractory element Re,the segregation tendency of the most alloying elements in WZ30 becomes more severe,leading to an increase in eutectic fraction and a higher freckling tendency.

关 键 词：第三代单晶高温合金 定向凝固 微观组织 共晶 元素偏析 

分 类 号：TG146[一般工业技术—材料科学与工程]