摘要:随着科学技术的发展，人们生活水平的提高，轻薄短小的塑料产品的使用率越来越高。在此类塑件成型的过程中，因为材料种类、工艺参数、模具设计的不同，可能会出现短射、翘曲变形、熔接线、缺料、缩水等缺陷，从而影响产品的成型质量和使用性能。因此，本文以薄壁塑件键盘后盖为例，模拟分析其注塑成型过程，优化工艺参数，并进行模具设计。首先，对塑件进行结构工艺性分析，选择原材料；其次，建立键盘后盖的有限元模型，模拟分析其注塑成型过程，确定浇注系统和冷却系统。然后，对比分析PC、ABS、PC+ABS三种材料对注射成型的影响，并基于正交实验方法优化成型工艺参数。最后，在此基础上进行模具设计，并绘制注塑模具的二维图和三维总装配图。

关键词：薄壁塑件；注塑成型；数值模拟；正交实验；模具设计

Abstract:With the development of science and technology, people's living standards improve the use of thin and small plastic products is getting higher and higher. In the process of forming such plastic parts, due to the type of materials, process parameters, mold design, there may be short-shot, warping deformation, welding line, lack of material, shrinkage, surface images, air, burr, Surface unclean and other defects, thus affecting the product molding quality and performance.

In this paper, the thin-walled plastic back cover as an example, simulation analysis of its injection molding process, optimize the process parameters, and mold design. First of all, the plastic parts of the structural process analysis, to determine the feasibility of its injection molding. Second, select the type of raw material and determine the specific grade. Then, the finite element model of the back cover of the keyboard is established, and the filling process is simulated and analyzed. The pouring system is determined. The cooling process is simulated and the cooling system is determined. Then, the effects of PC, ABS, PC + ABS and their effects on injection molding were compared and the  process parameters were optimized based on orthogonal experiment. Finally, on this basis,  the mold design, and get injection mold two-dimensional  map  and three-dimensional assembly map.

Keywords: Thin-walled plastic parts; injection molding; numerical simulation; orthogonal experiment; mold design

目录

第一章绪论 1

1.1研究背景 1

1.2薄壁塑件的研究现状与发展 2

1.3本文的主要研究内容 3

第二章薄壁塑件成型及其CAE原理 5

2.1键盘后盖的工艺性分析 5

2.2原料的选择与分析 5

2.3注塑成型CAE的工作原理及模拟分析流程 7

2.3.1Moldflow软件的工作原理 7

2.3.2模拟分析流程 7

第三章键盘后盖注射成型过程模拟分析 9

3.1有限元建模 9

3.2浇口分析及浇注系统的建立 10

3.3冷却系统的分析与确立 13

3.4不同材料对注塑成型的影响 16

3.5基于正交实验的工艺参数优化 19

第四章键盘后盖的注塑模具设计 22

4.1注塑模具的模架选择