摘要
Investigations on the fabrication of large-size lightweight Mg alloy components by wire-arc directed en-ergy deposition(DED)are steadily flourishing.Nevertheless,most of these components still suffer from inferior performance due to internal defects and inherent columnar grains.Herein,external ultrasound fields with different powers were successfully introduced into the wire-arc DED of AZ31 Mg alloy.The microstructure,defects,and mechanical properties of the fabricated components were carefully charac-terized and compared.The results show that the external ultrasound fields lead to decreased porosity,complete columnar to equiaxed transition(CET),and enhanced performance.Consequently,the UA90 samples exhibited a remarkable increase of~30%,~45%,and~189%in yield strength,ultimate tensile strength,and elongation,respectively.The dominant mechanisms of enhanced strength-ductility synergy were analyzed in detail.This study thus sheds new light on wire-arc DED of Mg alloy components with excellent performance via external ultrasound fields.
基金
National Natural Science Foun-dation of China(Nos.52275374,52205414)
Xiaomi Founda-tion through the Xiaomi Young Scholar Program,the Key Research and Development Projects of Shaanxi Province(No.2023-YBGY-361)
as well as the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)
State Key Laboratory for Mechan-ical Behavior of Materials(NO.20212311)
as well as the Xi’an Jiaotong University Basic Research Funds for Freedom of Explo-ration and Innovation-Student Programs(NO.xzy022023066).
