空心风扇叶片高循环疲劳异常失效分析.pdf

研究论文 RESEARCH 空心风扇叶片高循环疲劳异常失效分析 王家广，李　迪，陈云永，刘晓锋，廖连芳 （中国航发商用航空发动机有限责任公司设计研发中心，上海 200241） [ 摘要 ] 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。 关键词：空心风扇叶片；高循环疲劳；异常失效；超塑成形；断口分析 Analysis of Hollow Fan Blade Unexpected Failure in the HCF Test WANG Jiaguang, LI Di, CHEN Yunyong, LIU Xiaofeng, LIAO Lianfang (Design, Research Development Center, AECC Commerical Aircraft Engine CO., LTD., Shanghai 200241, China) [ABSTRACT] 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. Keywords: Hollow fan; High cycle fatigue;Unexpected failure; SPF; Crack analysis DOI: 10.16080/j.issn1671-833x.2017.12.084 某空心风扇叶片尺寸大，结构复杂，具有小展弦比、 大扭角、复合弯掠等典型设计特征 [1-2] ，其瓦伦空心结构 1　试验过程及失效描述 控制参数多，且内部空心瓦伦结构采用扩散焊接 / 超塑 针对某空心风扇叶片开展了试验目标循环数为 7 成形等特种工艺实现，尤其是压力、温度、时间等对瓦伦 1×10 的振动疲劳试验，叶片材料为 TC4，试验考核振 空心结构的成形质量影响很大的热成形工艺关键参数 型为一阶弯曲振型。