B50A789第1级静子叶片裂纹缺陷分析

采用B50A789材料制备的压气机叶片产生的缺陷，主要是由于原材料内部夹杂、局部偏析、组织粗大，带状偏析和折叠引起的。本研究采用金相和能谱分析方法研究了锻造压气机叶片表面裂纹的形成机理，并对其锻造裂纹的形成过程进行有限元模拟。结果表明:结合低倍及高倍形貌特征，可以得出叶片缺陷为锻造加工过程产生的折叠裂纹；通过有限元模拟分析认为锻造叶片表面裂纹是源于锻件在制坯过程中，在连接杆与安装圆盘的转接处形成啃伤台阶，导致终锻结束时在叶身形成折叠裂纹缺陷。同时通过对试验过程中锻造工艺调整，采用分料卡子对过渡区分料或进行打磨来保证转角半径圆滑过渡，可有效避免叶片表面折叠和裂纹缺陷的形成。

Cracking Analysis of First Stage Stator Vane Made of B50A789 Steel

The defects of the compressor blades made of B50A789 steel are mainly due to inclusions of raw material, local segregation, coarse structure, zonal segregation and folding.In this paper, the forming mechanism of surface crack of forging compressor blades was analyzed by metallographic examination and energy spectrum analysis, and the forming process of cracks was simulated by infinite element analysis.The results show that the crack of the blade is folding crack forming during the process of forging.The results of finite element simulation show the surface crack of the blades initiated during the production process of the blank.Nicking steps formed at the transfer zone between connecting rod and installation disc, leading to folding crack at the blade body when forging process was finished.The formation of the blade surface folding and cracking defects can be effectively avoided by the improvement of the forging process and using feed clamps or polishing to ensure the smooth transition of the blade blank.