激光立体成形Ti_2A1Nb基合金组织演化  

Microstructure Evolution of Ti_2AlNb-based Alloy by Laser Solid Forming

作　　者：姜国政[1] 陈静[1] 林鑫[1] 赵晓明[1] 黄卫东[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》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

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.

关 键 词：激光立体成形(LSF) TI2ALNB基合金 组织 O相 

分 类 号：TG146.23[一般工业技术—材料科学与工程]