Formation of Stray Grains in Directionally Solidified Ni-based Superalloy with Cross-section Change Regions

摘要：

　　The formation mechanism of stray grains in cross-section change region of casting clusters for single crystal superalloy DD483 were investigated experimentally during the conventional directional solidification.The results showed that the stray grains formation was different on the two sides of the platform.Indeed,stray grains formation in the region of the cross-section change on the shadow side showed a high probability,while the heater side,no stray grains appeared.Additionally,the cooling curves at the cross-section change region also showed that the distribution of temperature was different on the two side of the platform.The formation of stray grain can be attributed to the local undercooling at the cross-section change region is exceed the critical undercooling for nucleation,led to the heterogeneous nucleation,while the asymmetric temperature distribution should be responsible for asymmetrical formation of stray grains on the two sides of the platform.

关键词： Cross-section change:Directional solidification:Superalloy:Stray grains.

作者: Weidong Xuan Zhongming Ren Huan Liu Tingsheng Tu

作者单位: Shanghai Key Laboratory of Modern Metallurgy & Materials Processing, Shanghai University,Shanghai 200072, China

会议类型: 国际会议

会议名称: the Chinese Materials Congress 2012(2012年中国材料大会(CMC2012))

会议地点: 太原

会议语种:英文

页码: 535-539

在线出版日期: 2012-07-13（万方平台首次上网日期，不代表论文的发表时间）