聚丙烯酰胺封孔工艺参数对铝合金微弧氧化膜封孔的影响

Effect of Polyacrylamide Sealing Process Parameters on Micro-arc Oxidation Film of Aluminum Alloy

采用扫描电镜观察表面形貌,利用电化学工作台测试极化曲线,研究了聚丙烯酰胺(HPAM)封孔工艺中封闭温度、封孔时间以及添加剂等参数对铝合金微弧氧化膜封孔效果的影响,并研究了加入添加剂后进行封孔试样的耐蚀性。结果表明,封孔温度越高和封孔时间越长,聚丙烯酰胺对铝合金微弧氧化膜层封孔效果越好。但是,温度超过60℃时会产生过渡交联,膜层表面变的粗糙且出现裂纹,封孔效果变差。相比不加添加剂三乙醇胺封孔的试样,封孔效果较好,铝合金微弧氧化膜层自腐蚀电位更高,自腐蚀电流更小,耐蚀性得到显著提高。

The surface morphology was observed by SEM. The polarization curve was tested by using electrochemical workbench test. The effects of polyacrylamide sealing process parameters on the micro-arc oxidation film of aluminum alloy were investigated, including sealing temperature, sealing time and additives, etc. And then, the corrosion resistance of the sealing samples after adding additives was studied. The results show that the higher sealing temperature and the longer sealing time, the effects of polyacrylamide sealing on the micro-arc oxidation film of aluminum alloy become better. However, when the temperature exceeds 60℃, transitional cross-linking appears, then the film surface becomes rough and cracks appear, and the sealing effect becomes poor. Compared with the sealing samples, without additive triethanolamine, the sealing effect is better, the self corrosion potential of aluminum alloy micro-arc oxide film layer is higher, then, the self corrosion current is smaller, and the corrosion resistance improves significantly.