Abstract: The good air sealing performance of body has a significant contribution to the noise, vibration, harshness (NVH) performance of the automobile. In order to improve the airtightness of the body in white of a certain model, all the end factors related to the quality of parts, process and engineering design are collected through the failure mode analysis of two leakage paths of the body sheet metal cavity and sheet metal gap. Through comparative analysis, the important factors affecting the air tightness of the target vehicle body in white are identified as Baffle size and quality, Baffle skeleton structure, Baffle foam structure and sheet metal lap surface and lap edge sealant road, and the effective optimization scheme are formulated according to these four key factors, which provides a systematic solution and method for improving the air tightness of the new vehicle model.

Key words: Body in white; Air tightness; Baffle; Sealer

摘要： 优良的车身气密性对汽车噪声、振动与声振粗糙度（NVH）性能来说至关重要。研究 以提升某车型白车身气密性为目标，通过对车身钣金腔体和钣金缝隙两种泄漏路径进行失效 模式分析，收集了所有与零件质量、工艺过程以及工程设计三个方面相关的末端因素。通过 对比分析，识别出影响目标车白车身气密性的重要因素为 Baffle 尺寸质量、Baffle 骨架结构、 Baffle 发泡结构及钣金搭接面和搭接边的密封胶路，并针对这四种关键影响因素制定了有效 的优化方案，给后续新车型白车身气密性问题提供了一种系统性的解决思路与方法。

关键词: 白车身；气密性；膨胀胶块；密封胶