摘要
应用光学显微镜、透射电镜及X射线衍射研究了Ti—42at.—%Al和Ti—45at.—%Al两种合金的固溶处理后的快冷组织,证明其为过饱和的有序α_2单相组织,过饱和单相在1000-1100℃等温转变时,以准连续和不连续的机制分解成为γ+α_2两相。准连续转变中包括γ片析出和胞状化两个阶段,并在原始α_2晶界处形成锯齿形边界。
A supersaturated single phase ordered α_2 structure in as rapidly quenched al-
loys both Ti-42at.-%Al and Ti-45at.-%Al, after solid solution treatment, was revealed un-
der observation with optical and transmission electron microscope as well as X-ray
diffraction analysis. The supersaturated single phase may transform into a lamellar structure
of γ+α_2 with a discontinuous decomposition mechanism in Ti-42at.-% Al alloy and with a
semicontinuous decomposition mechanism in Ti-45at.-%Al alloy when it aged isothermally
in the two-phase range between 1000 and 1100℃. The semicontinuous transformation in-
volves two process: precipitation of primary lamellar γ phase and subsequent formation of
cellular microstructure, in result, the initial even grain boundaries of α_2 become sawtooth.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1993年第2期A049-A056,共8页
Acta Metallurgica Sinica
关键词
TIAL
相变
金属互化物
TiAl
dual phase γ+α_2
phase transformation
