当前位置: X-MOL 学术Metall. Mater. Trans. B. › 论文详情
Microstructure and Properties of Inconel 718 Fabricated by Directed Energy Deposition with In-Situ Ultrasonic Impact Peening
Metallurgical and Materials Transactions B ( IF 1.952 ) Pub Date : 2019-09-04 , DOI: 10.1007/s11663-019-01672-3
Yachao Wang, Jing Shi

Many inherent issues, such as the detrimental residual stress, columnar grains with anisotropy, and weak mechanical properties, have severely impeded the adoption of metal additive manufacturing (AM) techniques including powder bed fusion and directed energy deposition (DED) processes. In this study, a hybrid AM process that consists of layer-wise laser metal deposition (i.e., a DED process) and in-situ ultrasonic impact peening (UIP) was applied to obtain Inconel 718 superalloy workpieces. Also, for further property enhancement, a post-heat treatment was applied to the deposited material obtained by the hybrid AM process. Scanning electron microscopy and transmission electron microscope were used to investigate the microstructure morphology and reveal the underlying strengthening mechanism. Electron backscatter diffraction was employed to quantitatively study the microstructure resulted from the hybrid AM process and the post-heat treatment. The profile of residual stress along the depth direction was obtained through X-ray diffraction. The results demonstrate that this hybrid AM process is capable of producing high-quality metal parts with significantly refined microstructure, and beneficial compressive residual stress along the depth into surface. Severe plastic strains are introduced by UIP, and the resulted mechanical twinning and dynamic recrystallization play an important role in refining microstructure. The material microstructure is further refined down to 100 µm, and the texture anisotropy is significantly diminished after solution treatment at 980 °C for 1 hour. Under the as-built condition, in-situ ultrasonic peening alters the residual stress component from a tensile state to an overall compressive state with a maximum value of − 190 MPa within the range of measurement depth.
更新日期:2019-11-04

 

全部期刊列表>>
化学/材料学中国作者研究精选
ACS材料视界
南京大学
自然科研论文编辑服务
剑桥大学-
中国科学院大学化学科学学院
南开大学化学院周其林
课题组网站
X-MOL
北京大学分子工程苏南研究院
华东师范大学分子机器及功能材料
中山大学化学工程与技术学院
试剂库存
天合科研
down
wechat
bug