新型环保钝化膜的制备工艺及性能研究

Study on preparation process and properties of new environment-friendly passivation film

以硫酸和植酸作为原料,利用阳极氧化法,研究了一种铝及铝合金表面处理的新型环保钝化膜制备工艺,在6061型铝合金表面制备了一层钝化膜,采用硫酸铜点蚀法对膜层进行耐腐蚀性能的测试,利用扫描电子显微镜(SEM)和能谱仪(EDS)对钝化膜层的表面形貌以及成分进行测试,并以耐腐蚀性作为依据确定钝化膜制备的最佳工艺参数。结果表明,钝化膜层的表面呈凹凸不平并有少量孔洞的结构,其耐腐蚀性能优异,最佳制备工艺参数为:温度38℃,电压18 V,钝化时间20 min,硫酸与植酸的质量比为2。这种新型铝及铝合金表面处理的钝化膜制备工艺,将脱脂、水洗、钝化等几道工序合并为一道工序,简化了生产工艺、提高了生产效率、减少了用水量以及废水的排放量,节能环保。

Using sulfuric acid and phytic acid as raw materials,a new kind of environmental protection passivation film was prepared on 6061 aluminum alloy by anodic oxidation.The corrosion resistance of the film was tested by copper sulfate pitting method.The surface morphology and composition of the passivation layer were studied by scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The passivation was determined based on the corrosion resistance.The optimum process parameters for membrane preparation.The results show that the surface of the passivation film is uneven and has a small number of holes.Its corrosion resistance is excellent.The optimum preparation parameters are temperature 38℃,voltage 18 V,passivation time 20 min,mass ratio of sulfuric acid to phytic acid is 2.This new passivation film preparation process for surface treatment of aluminium and aluminium alloys combines degreasing,washing,passivation and other processes into one process,which simplifies the production process,improves production efficiency,reduces water consumption and wastewater discharge,and saves energy and environmental protection.