论文部分内容阅读
透射电镜观察表明,Al-4.11%Cu二元合金中θ′相在等径角挤压(ECAP)强变形中发生反复的弯曲变形,形成了亚结构,并从亚结构界面处开始发生溶解,而θ相则发生了折断和破碎,并从破碎θ粒子的尖角处发生溶解。X射线衍射及小角度X射线散射测试结果表明,θ′相粒子随强变形溶解得比θ快,θ′相粒子在尺寸较大时即开始随强变形溶解。热力学分析表明,θ′相在强变形中因为自身的应变增加了系统的应变能和粒子回溶的驱动力,促使其在强变形中的溶解。而θ相的溶解则是因为破碎粒子尖锐菱角表面能的增加造成的。研究表明,析出相粒子应变能与表面能都是强变形诱导析出相粒子回溶的驱动力,尤其是应变能的作用更大。
Transmission electron microscopy showed that the θ ’phase of Al-4.11% Cu alloy underwent repeated bending deformation during ECAP deformation, forming a substructure and starting to dissolve from the substructure interface. While the θ phase breaks and breaks, dissolving from the sharp corners of the broken θ particles. X-ray diffraction and small-angle X-ray scattering results show that θ ’phase particles dissolve faster than θ with strong deformation and θ’ phase particles begin to dissolve with strong deformation when their size is larger. Thermodynamic analysis shows that θ ’phase in the strong deformation due to its own strain increases the system’s strain energy and the particle back to the driving force of dissolution, to promote its dissolution in the strong deformation. The dissolution of the θ phase is due to broken particles sharp water chestnut surface energy caused by an increase. The results show that both the strain energy and the surface energy of the precipitated phase particles are the driving forces for the strong deformation-induced precipitation of the precipitated phase particles, especially the strain energy.