盐雾环境下浸银覆铜板的腐蚀行为

 采用交流阻抗(EIS)法研究浸银覆铜板在中性盐雾环境的腐蚀行为,并结合SEM/EDS表面分析手段,分析了腐蚀产物形貌和组成特点.研究表明,在盐雾环境中,覆铜板的浸银层起到了保护作用,在盐雾实验初始阶段,试样表面没有发生明显的腐蚀,具有较大的阻抗值.但由于氯离子对浸银层破坏作用,导致浸银层发生局部破损,阻抗随着实验时间降低.当长时间盐雾实验后,浸银层逐渐丧失保护作用,生成的铜锈层不断增厚,阻抗值增大,铜锈层对外部的腐蚀介质的传输起到主要的阻碍作用.

Corrosion Behavior and Law of Copper-Clad Laminate with Immersion Silver Layer in Salt Spray Environment

The corrosion behavior of Copper-Clad Laminate(CCL) with immersion silver layers in the neutral salt spray environment is studied by Electrochemical Impedance Spectroscopy(EIS). The surface morphology and the composition of corrosion products were analyzed by the SEM/EDS surface analysis methods. The results indicate that the immersion silver layers can protect the products in the salt spray environment. On the sample surface, no obvious corrosion could be seen in the initial stage and large impedance values were measured. But local damages would occur in the immersion silver layers due to the chlorides on the sample surface. The impedance values decrease with the test time. For a long salt spray test time, the immersion silver layers cannot effectively prevent corrosion reactions. The increase of the impedance values is due to the continued thickening of the copper rust layers, which prevent the incursion of harmful ions and the further corrosion of matrix.