Abstract: Automotive plastic bottom guard plate have functions such as protecting the vehicle bottom, guiding traffic and reducing noise. However, during the use of automobiles, the road environment is harsh, and plastic bottom guard plate may have quality problems such as deformation and cracking, affecting the overall performance of the vehicle and even endangering the safety of drivers and passengers. Therefore, how to avoid deformation and cracking of plastic bottom guard plate during the design and manufacturing process has become one of the important issues faced by the automotive industry. This article aims to analyze the failure reasons of deformation and cracking of plastic bottom guard plate during the vehicle road test, optimize the product installation structure in combination with computer aided engineering (CAE) simulation technology, and propose corresponding solutions. The results show that factors such as the installation and fixation form, structural design, material selection and manufacturing process affect the reliability of the bottom guard plate. By deeply exploring the causes of deformation and cracking of the bottom guard plate and the solutions, it is expected to provide certain design references for related industries.

Key words: automotive plastic bottom guard plate; deformation and cracking; structural design; manufacturing process; cause of failure; solution countermeasures

摘要： 汽车塑料底护板具有保护车辆底部、导流和降噪等功能，但汽车在使用过程中道路环 境恶劣，塑料底护板会出现变形开裂等质量问题，影响整车使用性能，甚至危及驾乘者安全。 因此，设计和制造过程中如何避免塑料底护板变形开裂成为汽车工业面临的重要课题之一， 文章旨在分析塑料底护板在整车路试中变形开裂失效原因，结合计算机辅助工程（CAE）仿 真技术优化产品安装结构，提出相应解决对策。结果表明，安装固定形式、结构设计、材料 选择及制造工艺等因子影响底护板的可靠性，通过深入探讨底护板变形开裂原因及解决对策， 以期为相关行业提供一定的设计参考。

关键词: 汽车塑料底护板；变形开裂；结构设计；制造工艺；失效原因；解决对策