【摘要】 采用电阻法和透射电镜观察研究了应力对Al-3.88Cu(质量分数, ％,下同)和Al-3.87Cu-0.56Mg-0.56Ag合金时效析出相的影响,结果表明:外加应力促进原子团簇或GP区的形成但延缓θ‘和Ω相的析出与长大;Al-Cu-Mg-Ag合金时效动力学过程存在一个调整微观结构演化的临界应力值,在大于该值的应力作用下将有助于原子团簇或GP区的析出;Al-Cu合金和Al-Cu-Mg-Ag合金时效过程中引入外加应力导致沉淀相择优取向;采用Eshelby弹性夹杂物理论计算外加应力与错配应力场间的相互作用可分析产生应力位向效应的原因.更多还原

【Abstract】 The process of stress aging for Al-3.88Cu and Al-3.87Cu-0.56Mg-0.56Ag was inves-tigated by electric resistivity measurement and transmission electron microscopy. The results indicate that external stress promotes the formation of clusters of GP zones, but retards the growth of θ’ and Ω phases. A threshold stress which modifies the evolution of microstructure is found in Al-Cu-Mg-Ag alloy. The application of the external stress during aging induces preferred orientation of precipitates θ’ and Ω in Al-Cu and Al-Cu-Mg-Ag alloys. The reason of stress oriented effect is analysed from the interaction between external stress and misfit strain by Eshelby elastic inclusion theory.更多还原