Al、Ti、Ta对镍基单晶高温合金组织和性能的影响

Effects of Al,Ti and Ta on Microstructure and Properties of Ni-based Single Crystal Superally

利用ISP 05 DS/SC定向单晶炉拉制单晶试棒,研究了Al、Ti、Ta含量对镍基高温合金组织和性能的影响。研究结果表明,铸态组织中Al、Ti、Ta主要分布于γ′相中。Al、Ti、Ta含量的提高可以提高Co、Cr、Mo在γ基体中的溶解度,同时,随着Al、Ti、Ta含量的提高,合金的固溶温度提高,错配度增大,γ′增强相的形貌也由椭球形转为方形。高温持久试验结果表明,Al、Ti、Ta含量的增加可以提高合金的持久寿命。

Effects of Al,Ti and Ta on microstructure and properties of Ni-based single crystal superalloy prepared by ISP-05-DS/SC furnace were investigated by testing both solvus temperature and mismatch degree . The results reveal that Al,Ti and Ta elements are mainly distributed in γ′ phase in as-cast microstructure. The solubility of Co,Cr and Mo in γ phase and solvus temperature as well as the enlargement of mismatch can be increased with increasing in Al,Ti and Ta content,which results in the morphology of γ′ phase changed from spherical to cubic structure. In addition,the enduring life of the superalloy at high temperature can be improved with the increase of Al,Ti and Ta content.