粉末合金轮盘关键部位多圆弧转接降应力研究

为了验证某型航空发动机粉末合金涡轮盘低循环疲劳寿命,在旋转试验器上进行了涡轮转子的低循环疲劳寿命试验。在试验过程中有轮缘凸块和配重块断裂飞出,导致试验失败,得出该低循环疲劳试验故障的主要原因是裂纹起始部位的局部应力偏高。通过建立故障部位的单圆弧、双圆弧和3圆弧局部模型进行有限元计算,研究了转接圆角处的应力与转接圆角半径的关系。研究结果表明:采用3圆弧转接方法对粉末合金涡轮盘寿命考核部位进行改进设计是最佳方案,降低了轮盘考核部位应力,提高了轮盘寿命,并通过了试验验证。

Analysis of Stress Reducing on Powder Metallurgy Turbine Disk Using Multi-arcs Method

In order to verify the low cycle fatigue (LCF) life of powder metallurgical turbine disk for an aeroengine, the LCF life experiment of turbine rotor was performed on the spin tester. The failure of test was due to the flange and counterweight fracture, and the intense local stress of the crack starting position resulted in the LCF life failure. The finite element calculation was conducted by building the single, double and multi-arcs of failure parts, and the relationship between the stress and radius of arcs was studied. The results show that the powder metallurgical turbine was improved using the multi-arcs method. It is the best mothod to reduce the turbine stress, which improved the turbine life, and the turbine passed the testing verification.