Enhanced strength and ductility of laser-directed energy deposition repaired IN718 superalloy via a novel tailored heat treatment  

作　　者：You Zhou Xuewei Fang Naiyuan Xi Xiaoxin Jin Kexin Tang Zhiyan Zhang Qi Zhang Yang Yang Ke Huang 

机构地区：[1]State Key Laboratory of Manufacturing Systems Engineering,School of Mechanical Engineering,Xi’an Jiaotong University,Xi’an 710049,China [2]State Key Laboratory for High-Performance Tools,School of Electromechanical Engineering,Guangdong University of Technology,Guangzhou 510006,China

出　　处：《Journal of Materials Science & Technology》2024年第32期86-101,共16页材料科学技术(英文版)

基　　金：support from the National Natural Science Foundation of China(Nos.52275374 and 52205414);the Xiaomi Foundation through the Xi-aomi Young Scholar Program,the Key Research and Develop-ment Projects of Shaanxi Province(No.2023-YBGY-361);as well as the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001).

摘　　要：High-quality repair of damaged Inconel 718(IN718)superalloy components can achieve great economic benefits.However,the directly double aging(DA)treatment by industrial standards,yields an inferior ductility on the repaired component than that of the wrought base metal.In this work,wrought IN718 components were repaired by laser-directed energy deposition(LDED),a novel tailored heat treatment(THT)schedule consisting of a short-term low-temperature homogenization,and subsequent DA was sub-sequently conducted to strengthen the repaired IN718 alloys.The microstructure evolution and mechan-ical properties of the DA and THT-treated repaired alloys were comparatively investigated.The results indicated that the THT effectively dissolved most of the hard brittle Laves precipitates in the deposition region with only slight coarsening of the grains in the substrate.As compared to the DA sample,the elon-gation of the THT sample increased remarkably by 88%with only a slight reduction of 19.2 MPa in yield stress.Moreover,the strain distribution of the THT sample was overall more even but then destabilized in a narrow abnormal coarsened grain region caused by the static recrystallization.In general,this study breaks through the limitation of the low ductility of the DA-treated repaired IN718 alloys and provides a promising way to further improve the mechanical properties.

关 键 词：Additive manufacturing Laser repairing Heat treatment schedule Mechanical properties Inconel 718 alloy 

分 类 号：TG1[金属学及工艺—金属学]