摘要
采用双重退火对Ti8LC合金进行热处理,测试其室温及高温拉伸性能,并采用扫描电镜对室温拉伸断口形貌进行观察,分析其断裂机制。结果表明,提高双重退火的第一次退火温度,初生α相含量减少,β转变组织逐渐增多,合金强度略有升高,塑性降低;该合金的室温拉伸强度比普通TC4合金高,塑性相当;拉伸断口特征明显,两种退火制度的试样断口均为微孔聚集型韧窝断裂。提高第一次退火温度,试样宏观断口上纤维区减小,放射区和剪切唇区比例增大,这是塑性下降的表现,与试验测得的性能数据相吻合。
The duplex annealing of Ti8LC alloy was carried out. The tensile properties at room-temperature and high-temperature were measured. The fracture morphology at room-temperature was observed by SEM. The breaking mechanism was analyzed. The results show that the volume fraction of primary α phase decreases while βtransition microstructure increases gradually, and the strength of the alloy increases but the plasticity decreases with the increase of annealing temperature in α＋β phase ride. The tensile strength of the alloy at room-temperature is higher than that of TC4 alloy, but their plasticity is the same. Meanwhile the fracture and impact toughness of the alloy increase. The analysis of SEM on the fracto-graphs of tensile specimens are performed, and the analysis results indicate that the alloy＇s fracture behavior is dimple.
出处
《热加工工艺》
CSCD
北大核心
2009年第12期137-139,141,共4页
Hot Working Technology
基金
国家“973”计划资助项目(2007CB613807)
新世纪优秀人才支持计划资助项目(NCET-07-0696)
