为定量测试喷射沉积合金GP区周围的晶格应变的分布,利用喷射成形技术制备了Al12Zn2.4Mg1.1Cu合金。随后对合金进行热挤压、758K固溶2小时和393K时效20小时处理。利用高分辨透射电子显微镜(High Resolution Transmission Electron Microscopy,HRTEM)和几何相位分析(Geometric Phase Analysis,GPA)软件对GP区的结构和应变场进行了测量和分析。结果表明,GP区附近的应变值在各方向差别较大,沿GP区惯习面法线方向的应变最大(εxx=-0.092),与惯习面平行方向上的应变最小(εyy=-0.004)。该项结果可解释GP区附近位错运动的差异:由于应变场在各方向上存在较大差别,产生的应变强化效果不同,导致阻碍位错运动的能力也有所不同。
In order to quantitatively measure the lattice strain distribution around GP zone,an Al12Zn2.4Mg1.1Cu alloy was prepared by spray deposition.Alloy samples were subsequently processed by hot extrusion,solid solution treatment at 758K for 2 hours and aging at 393K for 20 hours.The structure and strain field of GP zones in the alloy was experimentally investigated based on High Resolution Transmission Electon Microscopy(HRTEM) and geometric phase analysis(GPA).Experimental results show that obvious strain difference around GP zones are generated along different directions;the largest strain(εxx =-0.092)occures along the habit plane normal direction of GP zones,the minimum value(εyy =-0.004)occures along the habit plane parallel direction.Above results may explain the difference of hinder dislocation motion around GP zone.The difference of strain distribution along different directions around GP zone results in different strain strengthening effect,which causes the difference of hinder dislocation motion.