摘要
通过霍普金森压杆实验研究2519A铝合金T87,T8,T9和T9I64种形变热处理状态在1040~5900s^(-1)应变率范围的动态冲击变形行为,并利用金相、透射电镜等手段分析在动态变形中合金微观组织的演变规律,研究不同形变热处理工艺对2519A铝合金动态变形行为的影响。结果表明:与T87态合金相比,强冷变形的T8和T9态合金高速冲击的动态屈服强度大幅提升,但是合金的绝热剪切敏感性也显著增加,更容易发生绝热剪切开裂。断续时效T9I6工艺可以提高2519A合金强化析出相的密度,使θ'相(Al_(2)Cu)更细小弥散分布。这样降低了θ'析出相在高应变率下被位错切割分解的速率,提高合金在高速变形过程中的稳定性。2519A-T9I6铝合金在高应变率下拥有较高的动态屈服强度和较低的绝热剪切敏感性,在高速变形过程中表现最佳。
The dynamic deformation behaviors of 2519 A aluminum alloy treated by T87,T8,T9 and T9I6 were investigated by the split Hopkinson pressure bar in the strain rate range of 1040-5900 s-1,and the microstructure evolution of the alloys during high velocity impact were analyzed by means of metallography and transmission electron microscopy,the effect of different thermo-mechanical treatments on dynamic responses of aluminum alloy 2519A was revealed.The results show that the dynamic yield strength of 2519A-T8 or T9 aluminum alloy is increased significantly than T87 treated alloy,but the adiabatic shear susceptibility is dramatically improved.Interrupted aging T9I6 can improveθ’(Al2Cu)precipitates density and make them much finer and denser,which reduce the decomposition rate ofθ’precipitates and enhance its stability at high strain rate.So 2519A-T9I6 aluminum alloy has much higher dynamic yield strength,and lower adiabatic shear susceptibility,which shows best performance at high strain rate.
作者
孙大翔
董宇
叶凌英
唐建国
SUN Da-xiang;DONG Yu;YE Ling-ying;TANG Jian-guo(Guangdong Industrial Analysis and Testing Center,Guangzhou 510650,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)
出处
《材料工程》
EI
CAS
CSCD
北大核心
2021年第2期79-87,共9页
Journal of Materials Engineering
基金
广东省科学院实施创新驱动发展能力建设专项资金项目(2018GDASCX-0954)
广州市对外科技合作计划项目(201907010004)
广东省自然科学基金(2018A030310417)
2020年广东省省属科研机构改革创新领域稳定支持。
关键词
2519A铝合金
形变热处理
高应变率
动态屈服强度
绝热剪切敏感性
θ'析出相
2519A aluminum alloy
thermo-mechanical treatment
high strain rate
dynamic yield strength
adiabatic shear susceptibility
θ’precipitate
