(1. 中国科学院 金属研究所 沈阳材料国家(联合)实验室，沈阳 110016；
2. Department of Chemistry, University College London, London WC1H 0AJ)
摘 要: 采用XRD、TEM等手段对Ti-24Nb-4Zr-8Sn(质量分数，%)合金中温旋锻变形后的显微组织进行研究。结果表明，经过较大的中温变形后，合金呈旋涡状大理石花纹组织且具有与旋锻轴向平行的强烈的á110ñ丝织构，这种典型的组织是由于具有á110ñ取向的晶粒在轴向拉应力状态下发生平面应变所致。TEM分析显示组织中含有高密度的小角晶界，应变分布不均匀。旋锻变形后，合金具有3.3%的超弹性变形和微弱的加工硬化行为。由于变形组织中留有大量的分布不均匀的残余应力，合金的塑性较差，在600 ℃下5 min去应力退火处理后，合金的塑性增强。
关键字: Ti-24Nb-4Zr-8Sn；中温旋锻；织构；平面应变
warm-swaged Ti2448 alloy
（1. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences,
Shenyang 110016, China;
2. Department of Chemistry, University College London, London WC1H 0AJ）
Abstract:The warm-swaged structure of Ti-24Nb-4Zr-8Sn (mass fraction, %) was studied by XRD and TEM. The results show that the warm-swaged alloy presents a swirled marble-like structure and has a pronounced fibrous á110ñ texture along the swaging axis. This typical swirled structure forms owing to the planar strain deformation of the á110ñ-textured grains. According to the TEM observation, there are high densities of low angle grain boundaries, dislocations and asymmetric strain in the deformed structure. The warm-swaged alloy characterizes as prominent non-liner elasticity, 3.3% recoverable elastic strain, and trivial work hardening behavior. Due to the large and asymmetric strain, the plasticity of the deformed alloy is deteriorated, which can be improved after 5 min heat treatment at 600 ℃.
Key words: Ti-24Nb-4Zr-8Sn; warm-swaged; texture; planar strain
