Corrosion Behavior of AZ31 Magnesium Alloy in Highly Alkaline Environment

• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2017,（4）
• 页码范围: 367-375
• 页数: 9页
• 语种: 英文
• DOI: 10.1007/s40195-017-0549-8

摘要

Industrial components made with a magnesium-aluminum alloy AZ31 are often used in diverse engineering applications where component weight,strength,and durability are critical.Similarly as other Mg alloys,however,the AZ31 is susceptible to corrosion in alkaline environments.In this work,corrosion of commercial grade AZ31 alloy plate was examined in potassium hydroxide (KOH) using immersion and potentiodynamic studies.The results suggest that the concentration of AI and Mn in the alloy may govern the kinetics of micro-galvanic corrosion and the initiation of corrosion pits.Further,trace amounts of Ni in the AZ31 alloy were seen to enable formation of Ni(OH)2 surface layer,which may have further accelerated alloy corrosion due to its cracking and void coalescence.The effect of pH on the corrosion behavior of AZ31 was studied with reference to Pourbaix diagrams.