首页|增材制造异构组织TiAl合金热压缩过程中的显微组织演变及动态再结晶机制

增材制造异构组织TiAl合金热压缩过程中的显微组织演变及动态再结晶机制

扫码查看
原文链接
  • 万方数据
采用热压缩实验、光学显微镜(OM)、扫描电镜(SEM)、电子背散射衍射(EBSD)和透射电镜(TEM)研究了电子束选区熔化(SEBM)制备的Ti-48Al-2Cr-2Nb合金(摩尔分数,％)在1150 ℃和0.1 s-1条件下热变形过程中的显微组织演变和动态再结晶(DRX)机制.结果表明:合金的初始显微组织为沿打印方向交替分布的γ粗晶层和γ+α2+(α2/γ)细晶层.热变形初期,粗晶中形成有利于后续变形的变形孪晶,细晶区域发生少量动态再结晶(DRX).随着应变的增加,粗晶区和细晶区通过不同的再结晶机制形成大量的DRX晶粒.其中,细晶区的DRX机制为不连续动态再结晶(DDRX),粗晶区的DRX机制包括DDRX和连续动态再结晶(CDRX).
Microstructural evolution and dynamic recrystallization mechanisms of additively manufactured TiAl alloy with heterogeneous micro structure during hot compression
Microstructural evolution and dynamic recrystallization(DRX)mechanisms of a Ti-48Al-2Cr-2Nb(at.％)alloy prepared by selective electron beam melting(SEBM)during hot deformation at 1150 ℃ and 0.1 s-1 were investigated by hot compression tests,optical microscope(OM),scanning electron microscope(SEM),electron back-scattered diffraction(EBSD)and transmission electron microscope(TEM).The results show that the initial microstructure of the as-SEBMed alloy exhibits layers of coarse y grains and fine γ+α2+(α2/γ)lamellar mixture grains alternately along the building direction.During the early stage of hot deformation,deformation twins tend to form within the coarse grains,facilitating subsequent deformation,and a small number of DRX grains appear in the fine-grained regions.With the increase of strain,extensive DRX grains are formed through different DRX mechanisms in both coarse and fine-grained regions,involving discontinuous dynamic recrystallization mechanism(DDRX)in the fine-grained regions and a coexistence of DDRX and continuous dynamic recrystallization(CDRX)in the coarse-grained regions.

TiAl alloyselective electron beam meltingheterogeneous microstructurediscontinuous dynamic recrystallization(DDRX)continuous dynamic recrystallization(CDRX)

陶慧、李慧中、李佳慧、王丽、贺卫卫、谭孝芬、周睿、梁霄鹏

展开 >

中南大学材料科学与工程学院,长沙 410083

中南大学粉末冶金国家重点实验室,长沙 410083

中南大学有色金属材料科学与工程教育部重点实验室,长沙 410083

西安赛隆增材技术股份有限公司,西安 710016

香港城市大学材料科学与工程系,香港高等研究院,香港九龙 999077

展开 >

TiAl合金 电子束选区熔化 异构组织 不连续动态再结晶 连续动态再结晶

Shaanxi Province Key Research and Development Projects,ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of China

2023KXJ-0715227440252174381

2024

10.1016/S1003-6326(24)66603-3

中国有色金属学报(英文版)
中国有色金属学会

中国有色金属学报(英文版)

CSTPCD
影响因子：1.183
ISSN：1003-6326
年,卷(期)：2024.34(10)