真空去应力退火对TC18钛合金残余应力及组织性能的影响  

Influence of vacuum stress relieving annealing on residual stress and microstructure properties of TC18 titanium alloy

作　　者：张尧武[1,2] 曾卫东[1,2] 史春玲[3] 康超[1,2] 彭雯雯[1,2] 

机构地区：[1]西北工业大学材料学院,西安710072 [2]西北工业大学凝固技术国家重点实验室,西安710072 [3]西安飞机工业(集团)有限责任公司,西安710089

出　　处：《中国有色金属学报》2011年第11期2780-2785,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家重点基础研究发展计划资助项目(2007CB613807);国家新世纪优秀人才支持计划项目(NCET-07-0696)

摘　　要：在不同温度和时间下对TC18钛合金进行真空去应力退火处理,研究TC18钛合金真空去应力退火前后力学性能及残余应力的变化规律,观察去应力退火后的金相组织和拉伸断口形貌。结果表明:经真空去应力退火后,TC18钛合金的抗拉强度和屈服强度降低,冲击韧性、断裂韧性、伸长率和断面收缩率提高;残余应力消除效果显著;随着退火温度的升高,合金显微组织呈现规律性变化;当温度达到650℃以上时,α相明显减少,亚稳定β相显著增加,导致其强度下降,与力学性能测试结果相吻合;合金塑性提高,与断口形貌分析一致;最后,得到TC18钛合金的真空去应力退火制度为600～650℃和1～4h。The different temperature and time parameters were adopted in the vacuum stress relieving annealing processes of TC18 titanium alloy.The evolution of mechanical properties and residual stress was researched,the microstructures and SEM images of fracture surfaces were also observed.The results show that,after the vacuum stress relieving annealing,the tensile and yield strengths of TC18 titanium alloy decrease,while the charpy toughness,fracture toughness,elongation and area reduction increase.The removing effect of residual stress is remarkable.Along with the increases of the temperature of stress relieving annealing,the microstructure of the alloy changes regularly.When the temperature exceeds 650 ℃,α-phase decreases obviously,and the metastable β-phase increases dramatically.Thus,the strength of the alloy decreases,which coincides with the result of mechanical properties.Meanwhile,the plasticity increases,which coincides with the fracture appearance.Finally,the vacuum stress relieving annealing schedule is obtained to be 600-650 ℃ and 1-4 h.

关 键 词：TC18钛合金 残余应力 真空去应力退火 显微组织 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]