1, the appearance of the parts after electrophoresis, the surface should be free of any particles, roughness, lumps, traps, holes, pinholes, marks, water droplets, hanging flow, bottoming out and flaking, and the thickness of the electrophoresis layer should be uniform.

2、Thickness of electrophoresis layerThe thickness of electrophoresis layer should be 10-18um.

3、Electrophoresis layer adhesion scratching method: its spacing is 1mm, and then divided into 100 squares. Then use the adhesive tape to stick on it, after pulling it off instantly with force, the electrophoretic layer shall not fall off 20/100, otherwise it is regarded as unqualified. Rolling line scratch method: it is to use the adhesion tester to measure, the requirement is not lower than the level 5 in GB/T1720, otherwise it is regarded as unqualified.

4, electrophoretic layer hardness is generally determined by ploughing method, is the use of 2H pencil, the front end of the quill will be cut flush, and then it will be launched with the object to be measured at 45 degrees, if there is no scratch on the surface then it is qualified, otherwise it is unqualified.

5, electrophoretic layer corrosion resistance in 24 or 48 hours for neutral test, and then observe the edge of the specimen and its outer surface whether there is white, black or brown corrosion points, if so, it means unqualified.