【摘要】 在细化晶粒的传统机械热处理工艺中的过时效前引入冷轧预变形,研究预变形对AA2195铝锂合金过时效第二相粒子组态及最终再结晶组织的影响。结果表明:预变形明显降低了过时效第二相沿板材厚度方向分布的不均匀性,并大大减小长度为5～10μm的棒状第二相,显著增加尺寸为0.8～2.0μm的第二相,从而提高再结晶时的形核核心。与未采用预变形的板材相比,经60%预变形的板材经轧制和再结晶后表层的晶粒尺寸由未预变形的12.6μm减小至9.26μm,其纵横比由1.61减小至1.27;中心层晶粒尺寸由14.62μm减小至11.27μm,其纵横比由2.47减小至1.70。过时效前的轧制预变形明显细化并等轴化AA2195铝锂合金的晶粒。更多还原

【Abstract】 In order to investigate the effects of the pre-deformation on second phase particles and recrystallization of AA2195 Al-Li alloy, cold-rolling pre-deformation prior to overaging was exploited in the traditional thermo-mechanical processing for grain refinement.The results show that the pre-deformation reduces the non-uniform distribution of the second phase particles along thickness of the plate, decreases the large rod particles with length of 5-10 μm and increases the particles with diameter of 0.8-2.0 μm dramatically, which results in increasing nucleation sites of recrystallization.In comparison with the sheet without pre-deformation, subsequent rolling and recrystallization decrease the final grain size and grain aspect ratio from 12.6 μm and 1.61 to 9.26 μm and 1.27 in the surface layer, and decrease the grain size and grain aspect ratio in the center layer from 14.62 μm and 2.47 to 11.27 μm and 1.70.Pre-deformation prior to overaging remarkably refine and spheroidize the grain structure of AA2195 Al-Li alloy.更多还原