摘要
采用平面分流模具热挤压成型制备了内部镶嵌钢芯的AZ31镁合金牺牲阳极,研究了挤压温度对其成形性能、显微组织、电化学性能以及在模拟土壤环境(饱和CaSO4-Mg(OH)2溶液)中腐蚀形貌的影响。结果表明:当挤压比为12,挤压温度为320~410℃时,AZ31镁合金阳极表面成形良好;晶粒尺寸随着挤压温度的升高先减小后增大,最小晶粒尺寸达到12.2μm;随着挤压温度的升高,镁合金电流效率和开路电位均先增大后减小,而表面腐蚀程度先减轻后加深,当温度为380℃时,电流效率和开路电位达到最大,分别为63.93%,-1.586V,此时表面点蚀孔数量最少,腐蚀程度最轻。
AZ31 magnesium sacrificial anode containing a steel core was fabricated by hot extrusion using plane porthole dies,and the effects of extrusion temperature on the surface quality,microstructure,electrochemical property and corroded surface morphology of the magnesium anode in saturated calcium sulfate-magnesium hydroxide solution were investigated.The results show that the magnesium anodes with high appearance quality was obtained when the extrusion ratio reached 12 and temperature varied between 320 to 380 ℃;the grain size of the magnesium alloy first decreased then increased with the increase of extrusion temperature,and the minimum grain size reached 12.2 μm;with the extrusion temperature increase,the current efficiency and open circuit potential of the magnesium alloy first increased then decreased,while the corrosion degree first reduced then accelerated.At 380 ℃,the current efficiency and open circuit potential reached the largest value of 63.93% and - 1.586 V, meanwhile the surface pits quantity was the least as the corrosion degree was the lightest.
出处
《机械工程材料》
CAS
CSCD
北大核心
2015年第10期32-36,共5页
Materials For Mechanical Engineering
基金
陕西省科技厅科技基金资助项目(2011JE009)
陕西省教育厅科技基金资助项目(12JS034)
关键词
镁合金阳极
热挤压
点蚀
挤压温度
电化学性能
magnesium anode
hot extrusion
pitting corrosion
extrusion temperature
electrochemical property
