2090铝锂合金T1相的强化作用及微量Ce的影响
来源期刊:中国有色金属学报1999年第3期
论文作者:赵志龙 李晓玲 徐磊 韩栋 陈铮
文章页码:546 - 551
关键词:铝锂合金; T1(Al2CuLi)相;强化作用
Key words:Al-Li alloy; T1(Al2CuLi)-phase; strengthening effect
摘 要:利用TEM技术观察和分析了2090和2090+Ce两种合金中,位错与T1相之间的交互作用行为,发现T1相与位错间的交互作用是一种切过和绕过的混合型;并利用脱溶相强化理论建立了相关的物理模型。实算结果表明,在190℃时效3~48h,T1相的强化作用约占总的临界剪切应力(CRSS)的30%~60%,其强化作用随时效时间的延续而增强,但过时效后增强作用平缓。2090和2090+Ce两种合金对比结果表明,在欠时效时,两合金中T1相的强化作用没有多大差异,而过时效状态下,含Ce合金中T1相的强化作用略大于前者,在仅考虑切过机制的情况下这种倾向尤为明显。欠时效时两合金基体强化作用约相差3.2 MPa,而过时效时两合金基体的强化作用约相差8.7 MPa左右。
Abstract: The behavior of interaction between dislocation an d T1-phase was observed and analyzed by means of TEM technique. The observing results show that the interaction between dislocation and T1-phase is a mixture-type of cutting and around mechanism, and the physical model are established by theory of precipitates strengthening. The results of calculation illustrate that the contribution of T1-phase is about 30%~60% to the total critical resolved shear stress (CRSS), and that the strengthening effects of T1-phase in 2090 and 2090+minor Ce alloys are little different at under-aged condition, but the strengthening effect of T1 precipitates in alloy containing cerium is less bigger than that of 2090 not containing cerium under over-aged condition, especially the cutting mechanism is only considered. The difference between strengthening effect of matrix in two alloys is about 3.2 MPa under-aged and 8.7 MPa or so under over-aged condition.