摘要
利用SEM、XRD和TEM研究了激光立体成形(LSF,lasersolid forming)Ti2A1Nb基合金的组织演化规律。结果表明:激光立体成形Ti2A1Nb基合金沉积态组织由B2/β0相(ordered-bcc)和O相(orthorhombic)组成。沉积态的相组成及微观结构从成形试样顶部→中部→底部呈现从B2/β0固溶体→B2/β0+O魏氏体→B2/β0固溶体的变化,进而使得激光沉积态Ti2A1Nb基合金中间部位的显微硬度值最大,顶部与底部相当。合金显微硬度随激光功率的增大而增大。
Microstructure evolution and hardness distribution of as-deposited Ti2A1Nb-based alloy by laser solid forming （LSF） was investigated through SEM, XRD and TEM. The results indicate that the LSFed Ti2AlNb-based alloy was constituted of B2/β0 phase （ordered-bbc） and O phase （orthorhombic）. The as-deposited phase in the bottom and top area of the LSF Ti2AlNb-based alloy sample is B2 phase （Nb-based solid solution）, while the phase in the middle area is O phase Widmansthttem. The phase evolution through bottom→ middle--top is B2/β0→B2/β0＋O→BB2/β0o. Therefore, the microhardness of the middle area for LSFed as-deposited Ti2AlNb-based alloy is maximum, and that of the top and bottom is similar. The microhardness of the alloys increases with the laser power increasing.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2010年第3期437-441,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金重点项目(50131010)
新世纪优秀人才支持计划项目(NCET-06-0879)
"863"计划项目(2006AA03Z0449)
"973"计划项目(2007CB613805)资助
