Abstract:

Recently, engineering polymer material is applied widely in aerospace and automotive fields. Engineering plastic products manufactured by injection molding have to endure mechanical, thermal and other complicated service conditions when they work. Under the complicated load conditions, the magnitude of service stress in engineering plastic parts is associated with the structure safety of the engineering devices, especially with people's lives. Taking warpage and residual stress of a hemisphere polycarbonate product as the initial conditions of the mechanical analysis, this paper proposes an efficient service stress optimization strategy with respect to the process parameters and the structure of the product and cooling channel, which integrals injection molding analysis and mechanical analysis. The maximum service stress is finally reduced by using an optimization strategy based on Kriging surrogate model and EI method. The results indicate that the thickness of the product, melt temperature and packing pressure are critical factors to influence the service stress.

Key words: polymer processing, service stress, Kriging model, optimal design, product design

摘要：

近年来，航空航天、汽车等工程领域大量使用工程用高分子聚合物材料制备结构零部件。在复杂的工作环境下，工程用高聚物注塑成型零部件承受机械荷载、热荷载等服役条件，其服役应力的大小直接关系到工程设备的结构安全。将半球形聚碳酸酯（PC）制品的翘曲变形和残余应力作为服役的初始条件，建立考虑制品结构、模具结构以及工艺条件的服役应力优化模型，利用基于Kriging代理模型和EI加点法的序列优化方法，有效地降低了半球形聚碳酸酯制品的服役应力。结果表明，制品厚度、熔体温度和保压压力对服役应力影响较大。

关键词: 聚合物加工, 服役应力, Kriging模型, 优化设计, 产品设计