摘要
研究了电磁搅拌对Incoloy825高温合金凝固组织及凝固过程中溶质元素偏析的影响。结果表明,在合金凝固过程中,施加电磁搅拌能够有效细化晶粒组织,同时增加等轴晶比例。当电磁搅拌电流强度由150A增加到300A时,铸坯中晶粒尺寸由300μm减小至210μm,同时等轴晶含量由66.7%增至77.5%。未施加电磁搅拌的Incoloy825高温合金铸坯内部的宏观偏析和微观偏析均比较严重,通过施加电磁搅拌,引起熔体强制对流,使熔体内部传热和传质得到改善,同时增大了冷却速率使二次枝晶臂间距减小,并促进液穴内熔体成分的均匀化,大幅度降低了合金元素的偏析程度。
Effects of electromagnetic stirring（EMS）on the solidification structure and segregation of Incoloy825 superalloy billet were investigated.The results reveal that the EMS can refine the macrostructure and increase the ratio of equiaxed grain in Incoloy825 superalloy billet.With the increaseg of EMS current from 150 Ato 300A,the average grain size can be refined from 300μm to 210μm,and the ratio of equiaxed grain is increased from 66.7% to 77.5%.Absence of EMS,the macrosegregation and microsegration exhibit more serious,and with EMS,the forced convection caused by EMS can improve the heat transfer and solute transfer,decreasing the secondary dendrite arm spacing as a result of the cooling rate increase,which homogenizes the distribution of the solute.The EMS can inhibit effectively the macrosegregation and microsegregation of Incoloy825 superalloy billet.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2016年第6期561-565,共5页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金重点资助项目(50834009)
教育部科学技术研究重大资助项目(311014)
中央高校基本科研业务费专项资金资助项目(N090609001)
高等学校学科创新引智计划资助项目(B07015)
