铝型材挤压分流模具交互式3DCAD/CAE设计技术开发

【作者】 马健哲；

【导师】 毛大恒； 李积彬；

【作者基本信息】 中南大学 ， 机械设计与理论， 2002， 硕士

【摘要】 为了保证铝型材挤压模具的质量，延长模具寿命，人们已经在铝型材挤压模具CAD／CAE／CAM技术方面进行了长期和不懈的努力。但是，至今为止，铝型材挤压模具的CAD系统仍停留在二维模型的基础上，难以满足现代的设计要求。在模具加工方面仍以传统的车、铣等人工加工为主，使模具在同一制造条件下，往往有不同的生产稳定性和使用寿命。这说明铝型材挤压模具的3DCAM及在数控加工中心中进行自动加工的与否已成为生产出高质量、高稳定性铝型材挤压模具的瓶径。而铝型材挤压模具的3DCAD是实现3DCAM的前提和基础。同时，评价铝型材挤压模具设计的优劣也一直是困扰铝型材挤压生产业的难题。人们曾尝试用二维力场有限元简化铝型材挤压模具的三维力场，但这只局限于结构标准，简单的场合，而且得出结果与实际相差较大。只有对3D的模型进行三维的力场有限元模拟，才能真正与实际生产紧紧联系在一起，为生产提供有实用价值的信息。本文针对以上问题，进行挤压分流模三维CAD／CAE设计技术的探讨。 在模具CAD系统设计方面首先，根据国内外先进铝型材挤压分流模具设计、生产、使用的实际经验和数据，结合实际提出模具强度校核修正公式，总结了模具设计的步骤。然后分析挤压分流模CAD系统的需求，提出模具CAD系统的功能模型，进行铝型材挤压分流模CAD系统总体设计。提供友好的人机交互式设计界面，将模具设计参数转换为三维建模参数。以数据文件形式，统一数据类型，实现系统数据共享。并提出以分流模模型的“基本骨架”为设计模型的思想，实现模具设计的参数化。采用由部分到整体的建模方法，减少建模参数间的依赖性。最后，在三维建模软件UGⅡ17.0的二次开发环境中以VC＋＋6.0为开发工具，开发出满足实际生产需要的挤压分流模三维CAD系统设计软件。 在挤压模具CAE方面首先，根据模具装配情况和实际挤压过程，对挤压力计算公式进行分析，提出了模具各部分受力负载的计算公式，确定模具在挤压过程中的受力状态和边界条件。然后，为了能真实地模拟实际生产过程，进行铝与模具钢在一定表面粗糙度、不同温度条件、不同润滑接触状态下的最大静摩擦系数实验，总结摩擦系数随温度变化的规律性和取值范围； 最后，应用UGⅡ17.0三维有限元CAE模块进行模具三维力场分析，根据三维有限元的结果分析，对模具危险部分进行预变形的处理和优化，改善模具受力变形的状况。 通过对铝型材挤压分流模具三维CAD／CAE技术的探讨，基本实现模具设计，分析、硼的整个过程，并开发出能实际使用的挤压分流模CAD系统，实现模具设计参数化和人机矩式设计，并进行分流模三维力场的有限元分析，对模具关键部位的形变进行控制，瞻具准确评价。上述的研究工作对促进我国铝型材挤压技术的发展有积极的推动作用，具有良好的经济效益和社会效益。更多还原

【Abstract】 In order to improve the quality of the extrusion mold and reduce the cycle time, a lot of research about CAD/CAE/CAM of system the extrusion die have been done. But most of the CAD systems are designed which are based on 2D system. It is so limited that it will not meet the need of modern mold industry any longer. Both design and precision of the machining are the important factor of affecting extrusion die’s life and quality. Machining the die by using the automatic machining center can improve it. So a 3D model of die must be provided by 3D CAD system. Using 3D FEM to analyses the die may be the best way to simulate the extrusion process of die in practices. On this situation, it is important to design a 3D CAD system for selecting mold and providing a method of analyzing the die by 3D FEM. The following have been performed in this paper:1. 3DCAD designing of extrusion die.Collecting a lot of information about mold’s design, a formula of giving the best height of mold and the process of mold’s design is provided, which can meet the need in practices. And the general structure of CAD system had been designed. The interface between computer and designer had been provided. Both using the data file to transfer the data and using the parametric technology to constraint relationship between the key structure of the mold are two characteristics of this 3D-cad system. The best construction method had been used to create 3D model of mold. Moreover, the 3DCAD system is developed in UGH developing environment using VC++ 6.0 as the developing tools.2. CAE of the extrusion die.Based on the analyses of the expression of the extrusion’s force, the load and constraint condition of the extrusion die structure are defined. Some experiments have been done to make sure the friction coefficient between the aluminum material and 4Cr5MoSiVl steel in different working conditions. The 3D model of mold is analyzed in 3D FEM by using UGH. Base on the analyses result,some danger structure of the model have been found and some suggestions of the mold modification are given.Since doing a lot of research about the 3D CADVCAE technology, A 3DCAD system of selecting mold for aluminum material have been developed and the method of analyzing the 3D model is provided in this paper. The 3DCAD system for aluminum material developed automatically can perform the design of the selecting mould by feature modeling. The valuable information about the quality of mold is given by 3D finite element analyses. What have been done in the paper will contribute to the mold industry.更多还原