AZ91D镁合金表面磷酸锌转化膜最优工艺及其耐蚀性研究

Study on the Optimal Process and Corrosion Resistance of Zinc Phosphate Conversion Coatings on AZ91D Alloy

采用正交试验的方法,以耐蚀性为指标,探究了磷酸锌转化膜的最佳制备工艺.利用扫描电子显微镜和动电位极化曲线等表征手段,对转化膜的形貌和耐蚀性进行了研究。最佳的磷化液配方为:1.25g/L NaNO_3,3g/L C_6H_8O_7·H_2O,2.5g/L NaF,5.5g/L ZnO,12.5mL/L H_3PO_4。

In this paper, the optimum preparation technology of zinc phosphate conversion coating was studied by orthogonal test, and the morphology and corrosion resistance of the conversion coatings were studied by means of scanning electron microscopy and potentiodynamic polarization.The optimum formula of phosphating solution is: 1.25g/L NaNO3, 3g/L C6H8O7·H2O, 2.5g/L NaF, 5.5g/L ZnO, 12.5mL/L H3PO4.