厚板精冲计算机模拟及模具刃口优化分析word格式论文.docxVIP

优秀毕业论文 精品参考文献资料 摘 要 采用厚板精冲技术制备的产品，不仅具有足够的强度和刚度，而且成本相对较低， 产品使用寿命高，该技术广泛应用于重型汽车、农用机械、工程与建筑机械等领域。但 在厚板冲裁过程中也存在冲头工作条件恶劣、模具寿命过低、冲件产品质量差等问题。 由于厚板在精冲过程中材料的变形区域狭小，且以断裂方式结束，使得冲裁过程非常复 杂，理论研究存在很多困难，限制了厚板精冲技术的推广应用。近年来，厚板精冲作为 现代冲压技术的主要发展方向与开拓重点越来越引人关注，与之相对应的理论研究，也 显得日益重要。 本文从塑性力学的角度分析了精冲变形过程中影响材料塑性流动的力能参数，研究 了提高精冲变形区静水压力的各种途径；根据冲压成形原理分析了厚板精冲成形过程， 总结了影响断面质量的主要因素。采用刚塑性有限元法建立了合理的精冲工艺有限元模 型，进行了厚板精冲有限元模拟。利用 DEFOEM-3D 对厚度为 6mm 的 AISI-4140 钢的 精冲变形过程进行了模拟，获得了变形过程的应力应变场，并通过调整冲裁间隙、板厚 、 压边力、反压力等工艺参数，分析了断面质量及冲裁力的变化。 采用 DEFOEM-3D 模拟了波浪形刃口冲裁工艺，提出了波浪形刃口厚板精冲方案， 并分别与平刃冲裁进行了比较分析，得出了波浪形刃口对冲裁件断面质量和冲裁力的影 响规律。 研究结果表明：冲裁力随着板厚的增加而增加，适当增加压边力和反顶力，可以提 高冲裁件的断面质量，但反顶力的增加会加大冲裁力，缩短模具的使用寿命；波浪形刃 口可作为降低冲裁力的一种有效手段在厚板冲裁中加以运用。 关键词：厚板；精冲；断面质量；刚塑性有限元；波浪形刃口 ABSTRACT Many products obtained by thick -plate fine- bla nking technology have not only the adequate intensity strength and rigid ity, but also the lower cost of product ion and extended operatinglonger usage useful life. The technology has been widely used in ma ny fields industries ， such as heavy duty car, agricultural machiner y, engineer ing and construct ional machiner y. However, there are some problems in the fine bla nking process, such as a tough working condition of environmentofthe punch being pressed,, a shorting life of the die and a poor quality of cross-section ofthe bla nked parts. The thick -plate fine bla nking process is very complicated since the deformation is focused on the sma ll zone of the sheet meta l and ended with fracture occurrence , and . Tthere are ma ny theoret ica l basic problems to be solved on theoret ica l studies of thick -plate fine bla nking. Due to these difficultie s, which limits the wide application ofthis technology the spread and exploitation of thick-plate fine blanking are limited. As a major developing direction and an important project, the thick -plate fine bla nking technology catches the attention, and increasingly . Therefore, the corresponding theoret ica l studies on the