铜含量对铝镁硅合金板晶间腐蚀敏感性的影响

Effect of copper content on inter-granular corrosion sensitivity of Al-Mg-Si alloy sheet

为分析乘用车发动机罩用铝镁硅合金长时间在低温下工作出现的晶间腐蚀问题与材料化学成分的关系,通过模拟典型时效热处理条件下三种铜含量的铝镁硅合金晶间腐蚀试验,获得晶间腐蚀深度数据并进行对比。通过透射电镜(TEM)和X射线能谱仪(EDS)进一步分析晶界析出相的形貌和成分,阐释了铜含量对铝镁硅合金晶间腐蚀性能的影响。通过试验和分析,发现铜是影响铝镁硅合金耐晶间腐蚀能力的重要因素。

To analyze the relation between the intergranular corrosion and the material chemical composition of the magnesium aluminum silicon alloy for the passenger car engine hood,resulting from working for a long time under a low temperature,an intergranular corrosion test is carried out with three different copper contents in magnesium aluminum silicon alloys.By simulating the typical aging heat treatment conditions,the intergranular corrosion depth data is obtained and compared.Furthermore,the morphology and composition of precipitates at grain boundaries are analyzed by transmission electron microscopy(TEM)and energy dispersive X-ray spectroscopy(EDS)and the influence of copper contents on the intergranular corrosion performance of Al-Mg-Si alloy is explained.Through experiments and analysis,it is found that Cu element is an important factor affecting the intergranular corrosion resistance of Al-Mg-Si alloy.