真空去应力退火温度对TA15钛合金锻件组织和性能的影响

Influence of Vacuum Stress Relief Annealing Temperatures on Microstructure and Mechanical Property of TA15 Titanium Forging

对TA15钛合金锻件试块分别在580℃、610℃和640℃进行了保温360 min炉冷至80℃随后空冷的真空去应力退火。检测了试块的显微组织和力学性能,并与未经去应力退火的试块作了比较,以揭示去应力退火温度对TA15钛合金锻件组织和性能的影响。结果表明:经真空去应力退火的试块抗拉强度和屈服强度略有提高,断后伸长率、断面收缩率和冲击韧度变化不大;随着真空去应力退火温度的提高,试块组织中初生α相减少、尺寸减小。经580℃保温360 min炉冷至80℃空冷的试块具有较好的力学性能,抗拉强度达980 MPa,冲击韧度达62.5 J/cm^2。

TA15 titanium alloy test blocks cut from a forging were subjected to vacuum stress relief annealing which consisted of soaking respectively at 580℃,610℃,and 640℃for 360 min,furnace cooling to 80℃,and then air cooling.After this,the test blocks were tested for microstructure and mechanical property,and compared with those of the block not subjected to stress relief annealing for the purpose of discovering the effect of stress relief annealing temperatures on structure and properties of TA15 titanium alloy forging.The results demonstrated that the blocks subjected to stress relief annealing exhibited slightly higher tensile and yield tensile strengths and no obvious changes in elongation,reduction of area and impact toughness.In addition,as the vacuum stress relief annealing temperature increased,primary a-phase in the test block decreased in both amount and size.The test block undergoing vacuum stress relief annealing consisting of soaking at 580℃for 360 min,followed by furnace cooling to80℃,and then air cooling had better mechanical properties,tensile strength being as high as 980 MPa,and impact toughness coming up to 62.5 J/cm^2.