中文摘要：

研究了不同变形特性的Al—Cu合金相在等通道挤压（ECAP）和多向压缩（MAC）强塑性变形中的溶解行为。结果表明：可变形粒子θ″和θ′在强变形中由于自身的应变，产生了具有高能量的亚晶界和剪切变形带，导致溶解发生，且由于表面能的作用使溶解持续进行；而对于难变形的θ粒子而言，只有破碎后的尖锐菱角部分由于表面能的作用而发生溶解；相对纯剪切应力的ECAP方法，MAC方法由于压应力分量的作用能够在析出相内部更有效地引入应变能，从而加速其溶解。

英文摘要：

Based on equal-channel angular pressing （ECAP） and multi-axial compression （MAC）, the dissolution behavior of second phases in Al-Cu binary alloy during severe plastic deformation was investigated. The results show that, for deformable particles, such as θ″ and θ′, the dissolution occurs at subboundary and shear band creates due to particle deformation where Gibbs energy is quite high. The dissolution propagates due to the role surface energy. As for undeformed particles （θ） only those sharp comer and edge dissolve due to increasing the surface energy. Compared with ECAP, because of pure shear stress, the strain energy can be introduced into the precipitates more effectively due to compressive stress, the deformable particles thus dissolve more rapidly during MAC severe plastic deformation.