为了研究定向凝固涡轮叶片因不同部位显微组织不同而引起的宏观持久强度的差异,根据典型涡轮叶片几何特征,设计了两类叶片模拟件(缘板、叶冠模拟件)和对比试件(标准平板试件),开展了持久试验及对比研究,试验结果表明:缘板、叶冠模拟件的持久寿命分别为对比试件持久寿命的94.22%和75.65%.这说明了定向凝固涡轮叶片不同部位的持久强度存在差异,这种差异需要在定向凝固涡轮叶片结构、寿命设计中加以考虑.研究结果对提高定向凝固涡轮叶片设计水平、改进定向凝固成形工艺具有重要意义.
In order to study the creep property variation at different regions on a direc- tionally solidified (DS) turbine blade caused by mierostructure difference among those re- gions, three types of DS specimen (platform-like specimen, shroud-like specimen and sheet specimen) were presented to investigate the difference by creep rupture tests at elevated tem- perature. The tests data shows that the performance of platform-like specimen and shroud- like specimen are 94.22% and 75.65% of sheet specimens' performance, respectively. Therefore, the difference of creep property among different regions on a DS turbine blade should be considered in blade structure design and creep life assessment. The research re- sults may also help to improve the manufacture processes of directional solidification.