前纵梁电泳漆结合力差的原因分析与解决方法

Cause analysis on poor adhesion of cathodic electrocoating to front longitudinal beam and countermeasures

针对白车身零件前纵梁在整车电泳后漆膜结合力差的问题,对缺陷零件表面进行了扫描电镜分析,分析了不同批次零件的表面微观形貌,单件与焊接总成件的表面差异,以及电泳工艺过程等相关因素,得出结合力差的原因是零件存放时间太久及薄膜处理前表面洁净度低。解决措施为更改脱脂槽溶液。

Aiming at the poor adhesion of electrocoating on front longitudinal beam of a car body in white, the surface of the defective workpiece was analyzed by scanning electron microscopy. Some related factors such as the surface morphologies of different batches of workpiece, the differences between the surfaces of the workpiece before and after being welded in an assembly, and the electrocoating process were analyzed. It was found that the workpiece had been placed for a long time in storehouse and it could not be cleaned well prior to the thin film treatment. These were the main reasons for poor adhesion of an electrocoating on the workpiece surface. The solution to this problem was to change the degreasing solution.