大型覆盖件应变分布测量与缺陷分析

研究了用网格试验方法对冲压成形后覆盖件的塑性主应变分布进行测量的方法。分析了其原理、网格形式 及其特点、基于单元格均匀变形条件的四边形网格塑性主应变计算的相关理论和方法。以一汽车覆盖件冲压成形 的拉裂缺陷分析为例,采用网格试验法测量计算获得了该零件成形后的塑性应变分布情况,分析了根据测试结果进 行冲压质量诊断和改进冲压工艺的方法。结果表明,该方法为分析和解决覆盖件冲压成形缺陷,优化冲压工艺提供 了一种有效的辅助工具。

Determination of Strain Distribution and Forming Defects for Automobile Panel Stamped Parts

The grid experimental method to determine principal plastic strain distribution of auto-panel stamped parts is discussed. Detailed analysis of its principle, grid patterns and their characteristics, the theory and technique to calculate principal plastic strains of quadrilateral grids under homogenous forming condition are provided. Using the quality defects analysis of one automobile panel stamped part as an example, the principal plastic strain distribution of the part after stamping process is measured and calculated by grid experimental method. An effective way to deal with quality defects and improve product quality in terms of the measured results is analyzed as well. The practical experiment shows that this technique provides an effective way to analyze and solve auto-panel stamping problems and forming defects.