本丈以電化學阻抗法量測於抗指紋鋼(中碳鋼表面值有薄鋁)表面塗以面漆與增塗三聚磷酸鋁漆後於3.5%NaCI水溶液中的抗蝕性，由漫滯時間而取得連續數據的變化，得到反應中的電阻值與 電容值改變，隨著漫滯時間的增長則電容值上升電阻值下降，而利用此兩種(電阻值與電容值)特性更能說明增塗三聚磷酸鋁漆後的抗蝕性。

The electrochemical impedance measurements were carried out in a 3.5 % NaCI solution for Crcoated plain carbon steels. Steels with two types of surface paintings containing polyesters and with or without an extra layer of aluminum tripolyphosphate were studied in this work. The variations of capacities and resistance verse immersion time were investigated. Ithas found that the capacity increased but the resistance decreased with increasing immersion time which indicates the degradation of coating layers. Itis observed that the steel with an extra layer of aluminum tripolyphosphate has better corrosion resistance.