2019 Volume 68 Issue 4 Pages 92-97
A new time accelerated testing method of corrosion resistance for electrodeposition coating steel was proposed in this study. This method is to measure a cut off voltage on environmental corrosion factors obtained by linearly increasing voltage of 1 V･s－1 within a few minute working time, in order to shorten an evaluation span of coating steels. The cut off voltage was measured for the cation electrodeposition coating steels of different coating thickness and different baking conditions after the coating process. As a result, the cut off voltage increased with the increase in thickness and crosslink density of the coating layer. The cut off voltage was well related to the blister initiation cycle number obtained by a cyclic corrosion test. The effectiveness of this method was then recognized. And ion permeability tests and FTIR analyses intimated penetration of ions and adsorption processes into the electrodeposition coating layer.
