Effect of Ti-Hf-Zr-Cu-Ni high entropy alloy addition on laser beam welded joint of Ti2AlNb based intermetallic alloy
Effect of Ti-Hf-Zr-Cu-Ni high entropy alloy addition on laser beam welded joint of Ti2AlNb based intermetallic alloy作者机构:State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Friction Welding TechnologiesNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710072China
出 版 物:《Journal of Materials Science & Technology》 (材料科学技术(英文版))
年 卷 期:2022年第120卷第25期
页 面:214-226页
核心收录:
学科分类:080503[工学-材料加工工程] 0806[工学-冶金工程] 08[工学] 0804[工学-仪器科学与技术] 0805[工学-材料科学与工程(可授工学、理学学位)] 0703[理学-化学] 0802[工学-机械工程] 080201[工学-机械制造及其自动化]
基 金:funded by the National Natural Science Foundations of China(Nos.52075449,51975480 and U1737205) the Aeronautical Science Foundation of China(No.20185470007)
主 题:Laser beam welding Ti2Al Nb based intermetallics High entropy alloy Heterogenous nucleation
摘 要:TiAlNb based intermetallic alloys,a potential competitor for next-generation super alloys,are susceptible to high-temperature embrittlement due to nucleation of a metastable single B2 phase in the fusion zone(FZ)during laser beam welding(LBW).In this study,a high entropy alloy(HEA),Ti-Hf-Zr-Cu-Ni,was self-developed and introduced as an interlayer into laser beam welded joint(LBWJ)of Ti-22 Al-27 Nb to analyze its impact on the evolution of microstructure in the weld zone(WZ)and subsequently on joint *** examination was carried out through electron probe micro analysis(EPMA),electron backscattered diffraction(EBSD)analysis,high-resolution scanning transmission electron microscopy(HRSTEM)comprising bright field(BF),selective area electron diffraction(SAED)and high angle annular dark-field(HAADF)*** of the HEA into FZ of LBWJ triggered heterogenous nucleation during solidification,resultantly,fine-grained B2 with a greater proportion of high angle grain boundaries(HAGBs)was *** of Ti-22 Al-27 Nb LBWJ,prepared with an interlayer of HEA,was composed of planar,cellular,columnar and equiaxed dendritic grains;a solidification mode which was different from that observed in LBWJ prepared without adulteration of the *** impact of heterogenous nucleation during epitaxial solidification on mechanical properties was established through micro vickers hardness mapping and tensile test,conducted at room *** average hardness,343.5 HV,in the FZ of LBWJ prepared with an interlayer of HEA,was compatible with that of base material(BM),345 *** ultimate tensile strength(UTS),1062 MPa,and percentage elongation,11.2%,of the HEA tempered LBWJ were found in close approximation with that of BM,1060 MPa and 13.4%,respectively.A ductile mode of failure was observed during tensile test of the Ti-Hf-Zr-Cu-Ni supplemented LBWJ of Ti-22 Al-27 Nb,while quasi-cleavage mode of fracture was apparent in the joint of Ti-22 Al-27 Nb welded with