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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_4Al_3Si_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 effects of cryogenic rolling, room temperature rolling and subsequent annealing on precipitates, microstructure evolution (recovery, recrystallization and grain growth), mechanical properties and corrosion behavior of 6082 aluminum alloy were investigated. Differential scanning calorimetry, transmission electron microscopy and backscattered electron diffraction were used to study the precipitation kinetics and microstructure of the samples after cold rolling, room temperature rolling and subsequent heat treatment to investigate their mechanical properties. After 200 ° C annealing, the tensile strength and hardness (345 MPa and HV 127) of the cryogenically rolled specimens were higher than the tensile strength and hardness of the rolled specimens at room temperature (320 MPa and HV 115). The tensile strength and hardness of the cryogenically-rolled samples after 200 ° C annealing are increased because of the β ’’ phase precipitated in the aluminum matrix, resulting in greater Zener resistance than the room temperature rolled samples. Corrosion and pitting potentials (-1.321 V and -700 mV) were also improved in the cryostat samples compared with the corrosion and pitting potentials (-1.335 V and -710 mV) at room temperature. Cold-rolled samples have high dislocation density, Mg_4Al_3Si_4 precipitates dissolve into the matrix, and the corrosion resistance of the samples can be improved by forming passive protective layer and inhibiting the formation of galvanic cells.