摘要
对7085铝合金进行温度范围为350～450℃的恒应变速率热压缩实验,模拟其工业等温锻造过程。采用金相显微镜、扫描电镜、力学性能测试、剥落腐蚀测试以及应力腐蚀开裂(SCC)测试技术研究热变形温度对7085铝合金锻件的显微组织、力学性能、剥落腐蚀性能以及应力腐蚀性能影响。研究结果表明:在350和400℃下变形的合金在热压缩与压缩后缓冷过程中未发生再结晶,而在420和450℃下变形的合金再结晶迹象明显;7085变形态合金经固溶与时效处理后,合金时效态的再结晶程度以及平均晶粒尺寸随变形温度的升高而增大;7085合金时效态的室温强度随变形温度升高而减小,塑性降低不显著;不同温度变形的7085合金的断裂模式均为韧性断裂;随着变形温度的升高,7085合金T6态的抗剥落腐蚀与抗应力腐蚀性能降低。
The isothermal hot compression tests of 7085 aluminum alloy were carried out at a constant strain rate and temperatures from 350 to 450 ℃ to simulate the isothermal forging process.The effects of hot deformation temperature on microstructure,mechanical properties,exfoliation corrosion property and stress corrosion property of 7085 alloy were investigated by optical microscope,scanning electron microscope,mechanical property testing,exfoliation corrosion and stress corrosion cracking testing.The results show that the recrystallization during the isothermal hot compression process and subsequent slow cooling is not activated when the alloy is deformed at 350 and 400 ℃,respectively.However,the recrystallization happens obviously when the alloy is deformed at 420 and 450 ℃,respectively.After solution treatment and aging treatment,the recrystallization and mean grain size of the alloy increase with raising hot deformation temperature.With the increase of deformation temperature,the strength of aged 7085 alloy at room temperature decreases,but the elongation decreases a little.The fracture models of all aged alloys deformed at different temperatures are ductile fracture.The exfoliation corrosion resistance and anti-stress corrosion cracking properties of peak-aged 7085 alloys decrease with the increase of deformation temperature.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2011年第1期88-94,共7页
The Chinese Journal of Nonferrous Metals
基金
国家重点基础研究计划资助项目(2010CB731701)
国家自然科学基金委员会创新研究群体科学基金资助项目(50721003)
关键词
7085铝合金
热变形温度
显微组织
力学性能
剥落腐蚀
应力腐蚀
7085 alloy
hot deformation temperature
microstructure
mechanical properties
exfoliation corrosion
stress corrosion
