空心风扇叶片高循环疲劳异常失效分析

针对某空心风扇叶片试验件在高循环疲劳试验中出现的异常失效现象,完成了振动仿真分析和断口分析。仿真分析结果表明失效区域非应力集中部位,断口分析结果表明裂纹萌生于薄板与叶盆侧厚板交接部位,其失效模式为疲劳失效,失效机理为超塑成形环节局部区域薄板扭曲导致高循环疲劳试验中薄板与厚板发生摩擦,进而疲劳失效。基于以上分析,制定了优化超塑成形工艺参数并增加CT检测环节的改进措施。验证试验表明,改进措施有效,很好地解决了该异常失效问题。

Analysis of Hollow Fan Blade Unexpected Failure in the HCF Test

For the unexpected failure of hollow fan blade in the HCF test,vibration simulation and crack analysis was done.The results indicated that,the failure region was not the high stress region,and the crack initiates from crossing area of thin plate and thick plate in the suction side,which was caused by fatigue.The failure mechanism was that thin plate of local region distorted in the SPF process so that the thick and thin plates fret wore in the high cycle fatigue test,which induces the fatigue failure.Based on the fatigue analysis,improvement measure was made through both optimizing the parameters in the SPF process and adding CT inspection in the test process.Validation test showed that the improvement measure was effective,and the unexpected failure problem was solved successfully.