摘要：随着社会的发展以及机械制造产品的需求，锻造在生产实际中的运用也越来越广泛，镦粗作为锻造自由锻中的重要组成，在生产和制造中起着不可或缺的作用，然而在生产制造中，通常只会镦粗高径比小于3的工件，对于高径比大于3的工件，一般的镦粗已经不能实现了，会出现失稳现象，即工件的弯曲现象，这给生产和制造带来了很大的麻烦。

本次论文的设计就是来解决大高径比镦粗的失稳现象，通过设计合理的方案来设计出一套专门用来镦粗大高径比工件的模具，已达到防止失稳的目的。该次的论文设计将采用冷挤压的方式来实现镦粗，在模具中将使用一个冲头将工件缓慢的挤压到所设计的凹模型腔内，以实现得到想要的制件，在该次的设计中，需要先使用Pro/E软件画出所需要设计的模具，然后模具放入DEFORM-3D中进行仿真模拟，以便于找到该模具中出现的不合理以及各种缺陷问题，然后需要对原模具进行修正和改善，从而进一步的使模具更加完美和更加适用于生产和实际的需要，达到物超所值的目的。

关键词：大高径比；失稳；冷挤压；仿真模拟

Abstract：With the development of society and the demand of machinery manufacturing products, the use of forging in production practice is becoming more and more extensive. Upsetting is an important part of forging free forging and plays an indispensable role in production and manufacturing. In the production, usually only upsetting  the workpiece with a diameter ratio of less than 3, for the workpiece with a height to diameter ratio greater than 3, the general upsetting can not be achieved, there will be instability phenomenon, that is, the workpiece early bending To the production and manufacturing has brought a lot of trouble.

The design of this paper is to solve the phenomenon of large diameter ratio upsetting instability, through the design of a reasonable program to design a set of special upsetting large diameter ratio of the workpiece die, has reached the purpose of preventing instability. The design of the paper will be used to achieve the use of cold extrusion upsetting in the mold will use a punch will slowly squeeze the workpiece into the concave mold cavity to achieve the desired parts, In this design, you need to use Pro / E software to draw the mold you need to design, and then put the mold into DEFORM-3D for simulation, in order to find the mold in the unreasonable and a variety of defects, The need to modify and improve the original mold, which further makes the mold more perfect and more suitable for the production and practical needs, to achieve value for money purposes.

Keywords: Large diameter ratio；Instability；Cold extrusion；Simulation simulation

目 录

第一章 绪论 1

1.1锻造简述 1

1.2模锻的分类及镦粗的概述 1

1.3冷挤压的概述 1

1.4大高径比镦粗的国内研究 2

1.5Pro/E简介及应用 3

1.6DEFORM简介及其操作步骤 3

1.7本文主要内容 5

第二章 防失稳镦粗模具方案确定 6

2.1镦粗方式的选择及模具设计简明流程 6

2.2零件与坯料分析计算 7

2.2.1材料的公艺性分析 7

2.2.2坯料尺寸