Experimental Study on Performance Evaluation of Environment-friendly Insulation Coatings of Cold Rolled Non-oriented Electrical Steel Sheet

According to the user’s process and the actual usage of the products,a series of parallel experiments have been done to explore the suitable test method and evaluation index of corrosion resistance,high temperature resistance and adhesion of environment-friendly insulation coatings on cold rolled non-oriented electrical steel sheet. The results show that the advisable evaluation method is that the corrosion area is less than 5% and 20% after six hours and twelve hours neutral salt spray test respectively. The appropriate test method of high temperature resistance of the coatings is that the laminated samples are placed in the nitrogen gas protective furnace and then heated up to 750 ℃ and held for 2 hours,the coating is qualified to be of good high temperature resistance if it has no blister,crack,flake and powder. The proper evaluation method of coating adhesion is that the sample is bend deformed with 0T,the 3M adhesive tape is stuck on the deformation area,tore off and then immersed in the 5% CuSO₄ for 5 seconds,the coating adhesion is qualified to be okay if it has no obvious crack,flake or discolor.