微量氮对DD33单晶高温合金雀斑形成倾向的影响  

Effect of Trace Nitrogen on Formation Tendency of Freckle of a Single Crystal Superalloy DD33

作　　者：姜卫国 韩东宇 李相伟 董琳[1,2] 李凯文 肖久寒[3] 卢玉章[3] 李强[1,2] JIANG Wei-guo;HAN Dong-yu;LI Xiang-wei;DONG Lin;LI Kai-wen;XIAO Jiu-han;LUYu-zhang;LI Qiang(Weifang University of Science and Technology,Shouguang 262700,Shandong,China;Weifang Key Laboratory of HighTemperature Materials and Single Crystal Components Fabrication Technology for Advanced Engine System,Shouguang 262700,Shandong,China;Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,Liaoning,China;Centre of Excellence for Advanced Materials,Dongguan 523808,Guangdong,China)

机构地区：[1]潍坊科技学院,山东寿光262700 [2]潍坊市先进动力系统用热端材料及单晶部件制备重点实验室,山东寿光262700 [3]中国科学院金属研究所,辽宁沈阳110016 [4]东莞材料基因高等理工研究院,广东东莞523808

出　　处：《铸造》2023年第4期375-381,共7页Foundry

基　　金：国家自然科学基金项目(51674235)。

摘　　要：通过扫描电镜、能谱及差示扫描量热仪等手段研究了不同氮含量(0.0002%与0.005%)对DD33单晶高温合金中雀斑缺陷的影响。利用ProCAST与JMatPro分别模拟了铸件糊状区的形状与熔体流体粘度。结果表明:随氮含量的提高,合金凝固温度区间减小,枝晶间共晶体积分数减少,一次枝晶间距及糊状区流体粘度增大;粘度增加使糊状区热溶质对流强度及枝晶间液体径向补缩流动变弱,最终导致定向凝固过程中雀斑形成倾向降低。The effects of different nitrogen contents(0.0002%and 0.005%)on formation tendency of freckle of single crystal superalloy DD33 were investigated by scanning electron microscopy(SEM),electron dispersion spectroscopy(EDS)and differential scanning calorimetry(DSC)technology.ProCAST and JMatPro software were employed to simulate the mushy zone shape and the viscosity of melt liquid,respectively.The experimental results showed that the primary dendritic arm spacing and mushy zone fluidity viscosity increased with the increasing of the nitrogen content.On the contrary,the solidification temperature range and the volume fraction of interdendritic eutectic phases decreased with the increasing of the nitrogen content.The increasing of the fluidity viscosity weakened the intensity of the mushy zone thermal solution convection and the feeding flow of the interdendritic liquid along radical direction,resulting in the low formation tendency of the freckle during the directional solidification.

关 键 词：单晶高温合金 显微孔洞 糊状区 粘度 雀斑缺陷 

分 类 号：TG21[金属学及工艺—铸造]