摘   要：随着科学技术的快速发展，生产水平的不断提高，人们对于机械产品的需求也越来越高，这就推动了机械加工技术的进一步的发展和完善。在镦粗成形工艺中，我们经常会遇到长轴类锻件，这些锻件的高径比明显大于3，如果采用传统的锻压成形工艺，在镦粗成形过程，不但模具会出现失稳的现象，而且工件也会产生缺陷，这就大大地降低了经济效益。这就要求我们必须在长轴类锻件镦粗成形方面做更多的研究。

   本篇论文是关于长轴类锻件镦粗防失稳模具的设计，文中提出一个合理的降低镦粗高径比的成形方案，利用模具降低了镦粗的高径比，避免了失稳和缺陷的产生。首先我们在冲头套的保护下进行镦粗，然后再利用冲头将冲头套内的坯料挤压到凹模当中去，从而完成变形过程，最后顶出机构工作顶出零件。设计模具过程中，使用了Pro/E、DEFORM-3D等软件，先设计出三维造型，然后通过成形过程的仿真模拟，根据分析的结果来改进模具的结构。这样就能够降低生产的成本，缩短设计的周期，得到了更加合理的模具结构，提高了成形零件的质量和精度，同时增加了经济效益。

关键词：长轴锻件；大高径比；模具设计；防失稳；有限元数值模拟

Abstract：With the rapid development of science and technology, the continuous improvement of production level, people's demand for mechanical products is also getting higher and higher, which promoted the further development and improvement of mechanical processing technology. In the upsetting process, we often encounter long shaft forgings, the forging ratio of these forgings is significantly greater than 3, if the use of traditional forging forming process, in the upsetting process will not only die the phenomenon of instability, and Blank will also produce defects, which greatly reduces the economic benefits. This requires that we have to do more research on upsetting of long shaft forgings.

This paper is about the design of upsetting and anti-instability die for long shaft forgings. In this paper, a reasonable scheme to reduce the upsetting ratio is proposed. The use of mold reduces the upsetting ratio to avoid the instability and the occurrence of defects The First of all, we are under the protection of the sleeve upsetting, and then use the punch to the bush of the blank into the die which is taken to complete the forming process, and finally the use of the top out of the body parts. In the process of designing the mold, we used Pro / E, DEFORM-3D and other software to design the three-dimensional modeling, and then through the simulation of the forming process to improve the mold structure. This will reduce the cost of production, shorten the design cycle, get a more reasonable mold structure, improve the quality and accuracy of forming parts, while increasing the economic benefits.

Keywords: Long shaft forgings; Large diameter ratio; Mold design;prevent instability; Finite element numerical simulation

目  录

第一章  绪论 1

1.1 镦粗与传统镦粗工艺的概述 1

1.2 镦粗设备的现状与发展趋势 1

1.3 对长轴类锻件镦粗的研究 2

1.4 DEFORM软件的应用介绍 3

1.5 本篇论文主要研究内容 4

第二章  防失稳镦粗模具设计方案的确定 5

2.1 锻模设计的流程 5

2.2 镦粗工艺性分析 5

2.2.1 零件的分析 5

2.2.2 毛坯尺寸的计算 6

2.3 镦粗模具设计方案的确定 7

第三章  镦粗挤压防失稳模具结构设计 10

3.1 凹模结构设计 10

3.2冲头与冲头套结构设计 10

3.3顶出机构设计 11

第四章  镦粗挤压防失稳模具零件设计 13

4.1 上模座 13

4.2 上模垫板 13

4.3 上模板 14

4.4 冲头套 15

4.5 冲头 16

4.6 凹模 17