Abstract: In the trial production of the new car, the topcoat quality of the front and rear exterior panels are poor, mainly showing orange peel defects. In order to solve the orange peel defects before the mass production of the car, through the investigation of the key parameters of the topcoat and the process parameters of other proceduces, it is determined that the main influencing factors of orange peel defects are the surface appearance of the steel plate, painting materials and coating processes. After the optimization and the verification, the coating defects of orange peel on front and rear door panels are improved after the roughness of the steel plate is reduced from 1.264 μm to 0.8～1.0 μm, the varnish is changed from 1 K to 2 K, the varnish spraying flow is increased by 10%～15% and the chain speed is reduced by 6.4%.

Key words: Orange peel defects; Steel plate roughness; Painting materials; Coating processes

摘要： 在新车型试制过程中，前后外板面涂不良，主要表现为橘皮缺陷。为在车型量产前解 决该橘皮缺陷，通过面涂关键参数及其他工序过程参数排查，判断橘皮缺陷主要影响因素为 钢板外观、涂料及涂装工艺。经过优化及验证，钢板粗糙度由 1.264 μm 降低到 0.8～1.0 μm、 清漆为由 1 K 变为 2 K、清漆喷涂流量提高 10%～15%及链速降低 6.4%后，前后门外板面涂 橘皮缺陷得以改善。

关键词: 橘皮缺陷；钢板粗糙度；涂料材料；涂装工艺