1、 I 摘要 阶梯形零件是多种复杂形状的组合，其成形工艺较难，在工艺设计和变形方案的 制定上，有其独自的特点。这类零件一般可采用板料多道拉深来成形。但是对于本设 计中的阶梯方铝罩零件来说，其内外都呈现阶梯状且形状不一致辞，并且由于中间过 渡部分形状不规则，因此不可能用板材成形工艺成形，而只能采用挤压等其他方法成 形。对于复杂的阶梯形零件,一次挤压不容易达到预期成形效果。因此，一般采用有 预成形的多道次挤压工艺。 其中的关键是如何合理分配材料变形程度， 控制材料流动， 减少过度变形，从而得到合格的零件。本文探讨了阶梯方铝罩挤压的可行性，通过对 产品零件图的分析，制定了几种工艺方案并进行分析比较，在
2、选择最优方案的同时也 制定了工艺流程。在此基础上详细地介绍了阶梯方铝罩挤压模具的设计过程。采用冷 挤压工艺加工后，提高了零件的精度和表面质量，改善了强度和韧性，减少了切削加 工量，节约了原材料，提高了生产效率，也改善了零件的组织性能。 关键词：阶梯方铝罩，成形工艺，冷挤压，模具设计 II ABSTRACT Multi-step part is a combination, which is composed with various complicated shapes. Its forming craft is more difficult. So it has its own charac
3、teristic in the technological design and the distortion plan formulation. Generally, this kind of components can be formed with the technology of multi-drawing the sheet. However, the product in this paper is not so regular. Its shape has steps both in exterior and interior and the shape is irregula
4、r. At the same time, the middle transition part is so complex that it is impossible to adopt the drawing technology to form. Therefore, we need to consider the cold extrusion and other way to get the shape. It is no easy to achieve the anticipated formed effect with only one extrusion, because the step-shape is so complex. It should use multi-extrusion craft with pre-form forging. So the key is how to distribute rationally the distortion degree, control material flow, reduce the excessive deform
