基于二次热处理的电火花制孔重铸层去除工艺  

Technology for Removal of Recast Layer by EDM Based on Secondary Heat Treatment

作　　者：赵婉蓉 杨泽南 许骏杰 张朕 王立斐 王祯 张强 ZHAO Wanrong;YANG Zenan;XU Junjie;ZHANG Zhen;WANG Lifei;WANG Zhen;ZHANG Qiang(Science and Technology on Advanced High Temperature Structural Materials Laboratory,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China)

机构地区：[1]中国航发北京航空材料研究院先进高温结构材料重点实验室,北京100095 [2]东北大学轧制技术及连轧自动化国家重点实验室,沈阳110819

出　　处：《航空制造技术》2025年第5期121-126,共6页Aeronautical Manufacturing Technology

摘　　要：气膜孔冷却技术是提高涡轮叶片承温能力的有效手段,而气膜孔电火花加工产生的孔壁重铸层严重威胁着气膜孔的服役性能。为了消除重铸层,提出了一种通过二次热处理消除电火花制孔孔壁重铸层的工艺方法。试验发现,电火花加工所得孔壁重铸层表现为γ单相组织,内部存在孔洞和微裂纹,且存在成分偏析现象。随后对气膜孔进行固溶和时效的热处理,发现原重铸层区域形成了与基体一致的双相组织,成分分布均匀。同时,原重铸层区域与基体取向一致,确保了叶片整体的单晶特性。高温拉伸试验表明,重铸层的消除避免了孔壁缺陷的危害,并改变了断裂机制,提升了气膜孔的拉伸强度和延伸率。因此,所提出的基于二次热处理的电火花制孔重铸层去除工艺为高品质气膜孔的制造提供了可靠手段。Film hole cooling technology is an effective means to improve the temperature bearing capacity of turbine blades,while the recast layer on the hole wall caused by EDM processing of film holes is a serious threat to the service performance of film holes.In order to eliminate the recast layer,this paper puts forward a process method to eliminate the recast layer on the wall of EDM hole by secondary heat treatment.Experimentally,it was found that the recast layer of the hole wall obtained by EDM was γ single-phase organization,with internal holes and microcracks,and the phenomenon of compositional segregation existed.Subsequently,the heat treatment process of solid solution and aging of the film holes revealed that the original recast layer region formed a two-phase organization consistent with the matrix,with uniform composition distribution.At the same time,the original recast layer region was oriented in the same direction as the matrix,ensuring the overall single-crystal characteristics of the blade.The high-temperature tensile experiments show that the elimination of the recast layer avoids the hazards of the hole wall defects and changes the fracture mechanism,which improves the tensile strength and elongation of the film holes.Therefore,the proposed process of removing recast layer by EDM based on secondary heat treatment provides a reliable means for the manufacture of high-quality film holes.

关 键 词：涡轮叶片 气膜孔 电火花加工 热处理 重熔层 

分 类 号：TG1[金属学及工艺—金属学]