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研究深冷轧制、室温轧制和后续退火对6082铝合金析出相、显微组织演变(回复,再结晶与晶粒生长)、力学性能和腐蚀行为的影响.采用差示扫描量热仪、透射电子显微镜和背散射电子衍射研究深冷轧制、室温轧制及后续热处理样品的析出动力学和显微组织形貌,以探讨其力学性能.经200°C退火后,深冷轧制样品的抗拉强度和硬度(345 MPa和HV 127)比室温轧制样品的抗拉强度和硬度(320 MPa和HV 115)更高.200°C退火后深冷轧制样品抗拉强度和硬度得到提高是因为铝基体中析出β'相,与室温轧制样品相比产生更大的Zener阻力.与室温轧制样品的腐蚀和点蚀电位(?1.335 V和?710 mV)相比,深冷轧制样品的腐蚀和点蚀电位(?1.321 V和?700 mV)也得到提高.深冷轧制样品具有较高的位错密度,Mg 4 Al 3 Si 4析出相溶解到基体中,通过形成钝化保护层和抑制原电池的形成,使样品的抗腐蚀性能得到提高.

The influence of cryorolling (CR), room temperature rolling (RTR) and post annealing on precipitation, microstructural evolution (recovery, recrystallisation and grain growth), mechanical and corrosion behavior, was investigated in the present work. The precipitation kinetics and microstructural morphology of CR, RTR, and post annealed samples were investigated by differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and electron back scattered diffraction (EBSD) to elucidate the observed mechanical properties. After annealing at 200 °C, UTS and hardness of CR samples (345 MPa and HV 127) were improved as compared to RTR samples (320 MPa and HV 115). The increase in hardness and UTS of CR samples after annealing at 200 °C was due to precipitation ofβ' from Al matrix, which imparted higher Zener drag effect as compared to RTR samples. The improvement in corrosion and pitting potentials was observed for CR samples (?1.321 V and?700 mV) as compared to RTR samples (?1.335 V and?710 mV). In CR samples, heavy dislocation density and dissolution of Mg4Al3Si4-precipitates in the Al matrix have improved corrosion resistance of the alloy through formation of protective passive layer and suppression of galvanic cell, respectively.