Anomalous enhancing effects of electric pulse treatment on strength and ductility of TC17 linear friction welding joints  

作　　者：Xin Zhang Junjie Zhang Yunkui Yao Qingsong Qiao Lixing Zhao Leichang Liu Feng Jin Mei Zhan Hongwei Li 

机构地区：[1]Key Laboratory of High-Performance Manufacturing for Aero Engine,Ministry of Industry and Information Technology,Northwestern Polytechnical University,Xi’an 710072,China [2]Engineering Research Center of Advanced Manufacturing Technology for Aero Engine,Ministry of Education,Northwestern Polytechnical University,Xi’an 710072,China [3]Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment,Northwestern Polytechnical University,Xi’an 710072,China [4]School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,China [5]State Key Laboratory of Solidification Processing,School of Materials Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China

出　　处：《Journal of Materials Science & Technology》2024年第36期155-166,共12页材料科学技术(英文版)

基　　金：the National Science Fund for Distinguished Young Scholars(No.52225505);the National Sci-ence and Technology Major Project(No.J2019-VII-0014-0154);the National Natural Science Foundation of China(No.52005412);the Open Research Fund of State Key Laboratory of Precision Man-ufacturing for Extreme Service Performance(No.Kfkt2023-12)for financial supports given to this research.

摘　　要：Mechanical properties of TC17 titanium alloy undergo a significant reduction after linear friction welding(LFW),of which the strength and ductility are hard to be improved simultaneously by traditional aging heat treatment(AHT),seriously limiting the application of LFW in the manufacturing of TC17 titanium alloy blisks.To this end,the present work proposes to use electric pulse treatment(EPT)to enhance the strength and ductility of TC17 LFW joints simultaneously by improving its microstructure.The results show that,in comparison to the uneven distribution ofαphases in the welding zone(WZ),heat-affected zone(HAZ),and base metal(BM)zone after AHT,EPT can selectively homogenize theαphase distribution of WZ and HAZ without impacting the BM.The selective effect of EPT is reflected as the synergistic influence of the local Joule heating effect and the electron wind effect,which promotes the diffusion ofβphase stabilizing element Mo and leads to a competitive precipitation ofβphase andαphase in theαphase transition temperature range.The ratio ofαphase toβphase in the WZ and HAZ finally approaches an equilibrium point which is similar to that of BM,leading to a uniform distribution ofαphase and realizing the synergy of strength-ductility of LFW joint:the maximum strength increase observed is 12.9%,accompanied by a corresponding elongation increase of 122%(by AHT&EPT),and the maximum plasticity improvement is 185%,accompanied by a corresponding strength increase of 4.3%(by EPT for 1 h).This study provides essential insights for improving the strength and ductility of LFW TC17 titanium alloy blisks and enhancing the applications of LFW in aeroengine components.

关 键 词：Linear friction welding TC17 titanium alloy Electric pulse treatment Phase transformation Local joule heating effect 

分 类 号：TG1[金属学及工艺—金属学]