(南京理工大学 机械工程学院，南京 210094)
摘 要: 采用浸泡腐蚀、失重腐蚀以及电化学腐蚀中的动电位极化曲线、电化学阻抗谱等方法研究静液挤压AZ80镁合金经350 ℃退火热处理1、2和4 h后，在pH 6.1的0.1 mol/L Na2SO4溶液中的腐蚀行为。结果表明：退火热处理使得挤压后的AZ80镁合金晶粒发生再结晶，改变AZ80镁合金的组织和成分分布，可有效提高镁合金的腐蚀性能；但是热处理时间也会对合金的耐蚀性产生影响，其中经(350 ℃,1 h)退火热处理后，合金自腐蚀电位为-1.4501 V，腐蚀电流密度为0.02323 mA/cm2，耐腐蚀能力显著提高，表现出较好的综合性能。
关键字: AZ80镁合金；静液挤压；热处理；耐腐蚀性能
（College of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China）
Abstract:The effect of heat treatment (annealing at 350 ℃ for 1, 2 and 4 h, respectively) on the corrosion behavior of hydrostatic extruded AZ80 magnesium alloy tube was investigated by immersion tests, weightlessness corrosion, potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in the 0.1 mol/L Na2SO4 solution at pH of 6.1. The results indicate that the re-crystallization occurs in the hydrostatic extruded AZ80 magnesium alloy during annealing, which can effectively improve the corrosion performance of magnesium alloy for changing microstructure and composition distribution. However, the duration of heat treatment would affect the corrosion resistance of alloy, comparing to other samples heat treated for different times, the annealing one after 1h heat treatment time at 350 ℃ shows good comprehensive performance at the corrosion potential of -1.4501 V, corrosion current density of 0.02323 mA/cm2.
Key words: AZ80 magnesium alloy; hydrostatic extrusion; heat treatment; corrosion resistance
