浇注温度对Al-4.5Mg-3Si合金耐蚀性能的影响

Influence of Pouring Temperature on Corrosion Resistance of Al-4.5Mg-3Si Alloy

采用电化学工作站、扫描电镜、X射线衍射技术及激光共聚焦显微镜等研究了浇注温度对Al-4.5Mg-3Si合金耐蚀性能的影响。结果表明,随着浇注温度降低,Al-4.5Mg-3Si合金耐蚀性能升高。随着浇注温度从760℃降至720℃,Al-4.5Mg-3Si合金的自腐蚀电位从-1.324 1 V提高到-1.215 2 V,自腐蚀电流密度从1.531 4×10^(-5)A/cm^(2)降至1.272 6×10^(-5)A/cm^(2)。同时,质量损失由0.174 1 g降至0.027 0 g,是760℃时的15.5%,720℃时的腐蚀速率最低,仅为760℃时的14.00%。

The influence of pouring temperature on the corrosion resistance of Al-4.5Mg-3Si alloy was investigated by electrochemical work station, scanning electron microscope, X-ray diffraction and laser scanning confocal microscope. The results indicate that the corrosion resistance of Al-4.5 Mg-3 Si alloy tends to be increased with the decrease of pouring temperature. The corrosion potential of Al-4.5Mg-3Si alloy is increased from-1.324 1 V to-1.215 2 V, and the corrosion current density is decreased from 1.531 4×10^(-5)A/cm^(2)to 1.272 6×10^(-5)A/cm^(2). Meanwhile, the corrosion rate is the lowest at 720 ℃, which is 14.00% of that of ones at 760 ℃, and the weight loss rate of alloy is decreased from 0.174 1 g to 0.027 0 g, which is 15.50% of that of ones at 760 ℃.