研究AM60镁合金在3种(A、B、C)市售汽车发动机冷却液中的腐蚀电化学行为.极化曲线、电化学阻抗谱测试表明,冷却液A对AM60镁合金的腐蚀性最强,B腐蚀性略低于A,C腐蚀性最弱,最适于镁合金汽车发动机使用.冷却液对发动机镁合金材料的腐蚀性与其电阻有关系,电阻越大,腐蚀性越小;冷却液中的乙二醇和添加剂组分在镁合金表面的竞争吸附对镁合金的腐蚀行为也有重要影响.

The polarization measurements and electrochemical impedance spectroscopy(EIS) were used to study the corrosion electrochemical behavior of AM60 magnesium alloys in three kinds of commercial coolants for automobile engine.Results show that the tested commercial coolants are slightly corrosive to AM60 magnesium alloys and their corrosivity varies from coolant to coolant.The coolant C is the least corrosive among the studied commercial coolants and the coolant A is more corrosive than the coolant B and C.The coolant C appears to be the most promising coolant for automobile engine made by magnesium alloys.The coolant resistivity plays an important role in the corrosion of AM60 magnesium alloys in commercial coolants,and the competitive adsorption of coolant components(such as ethylene glycol and the additives) on AM60 surface is also responsible for the corrosion behavior.