2196铝锂合金重固溶-时效组织与性能研究

Study on Microstructure and Mechanical Properties of 2196 Al-Li Alloy during Re-aging and Re-solution

基于2196-T8511铝锂合金,对其进行重固溶-再时效处理,研究时效时间对其力学性能与组织演化的影响。结果表明：重固溶处理后的晶界清晰。再采用适当的温度和时间进行时效处理,合金可以回复到原始态的力学性能。2196铝锂合金的重新固溶-再时效析出相包括T1相（Al2Cu Li）、δ＇相（Al3Li）和θ＇相（Al2Cu）;较短时效时间可形成较多δ＇相和θ＇相。随着时效时间的延长,T1相逐渐增多,δ＇相和θ＇相减少;重新固溶-时效后,断口韧窝增加,仍以分层断裂为主。

Based on 2196-T8511 Al-Li alloy, the effects of aging time on the mechanical properties and microstructure evolution during re-aging and re-solution were investigated. The results show that, the grain boundary after re-solution is clear.The mechanical properties can recover to the original state by using appropriate re-aging temperature and time. The intragranular precipitates include T1（Al2 Cu Li）, δ＇（Al3 Li） and θ＇（Al2 Cu）. Re-aging for shorter time, more δ＇ and θ＇ precipitates are formed. With the aging time increaing, T1 precipitates increase, but θ＇ and δ＇ precipitates decrease. After re-solution and aging, the dimples of fracture increase and delamination fracture is dominant.