弹膛精锻加工过程数值模拟及工艺参数影响研究

【作者】 何润华；

【导师】 樊黎霞；

【作者基本信息】 南京理工大学 ， 机械制造及自动化， 2007， 硕士

【摘要】 枪管是一种厚壁空心管件，由线膛、弹膛、外表面三部分组成。在现行枪管加工工艺中，基本采取径向锻造线膛，机加工外表面与弹膛，生产效率低下，机加工出的弹膛部分组织细密性、耐磨抗蚀差，表面粗糙度难以保证。在弹膛的锻压过程中，其可行性、成形质量(含充满成形、折叠、组织缺陷等)、材料利用率以及如何降低锻压力、提高模具使用寿命等，都是在制定成形工艺时必须重点考虑的。本文针对弹膛成形中的锻压加工中的以上几点关键技术，基于有限元刚塑性理论使用Ls-dyna对其成形过程进行模拟，进行了如下工作：(1)分析了摩擦系数、轴向进给对于锻压力、应变分布的影响，降低了锻压力、改善了应变分布情况。(2)分析了坯料外径对于成形质量、锻压力、锻透程度、应变分布的影响，合理选择了坯料外径，很好地解决了充满成形问题，降低了锻压力、改善了应变分布情况。(3)分析了弹膛内锥面的高度及长度对成形情况的影响进行了分析，综合考虑在不同高度及长度下的成形及应变分布情况，得出了在成形加工中可以实现的极限高度及长度，为指导相关设计打下了坚实的基础。更多还原

【Abstract】 Gun barrel is a thick and hollow part which is composed with three characteristic surface: line chamber, chamber, outside surface.In the currently producing process, line chamber is generally produced by radial forging; the two other characters are made with machining. The shortcoming of machining is that the productivity is very low and it is very hard to guarantee the tolerance of inner radius and surface roughness of the chamber.The feasibility, stability, quality of forming(including brimming forming, replicate and organize disfigurement), material utilize efficiency and how to reduce load, how to improve life-span of mould are all emphasized when we work out forming techniques. In this paper, several key techniques are simulated with software Ls-dyna:(1)Analyze the change of load and strain distribute in different friction and feed; reduce the load and improve the uniformity of strain distribute.(2)Analyze the change of load, quality of forming, strain distribute in different diameter, improve the uniformity of strain distribution and the quality of forming, resolve the brimming forming by choosing a reasonable diameter.(3)Research the chamber length and height which will effect the quality of forming, find out the maximal height and minimum length which can be obtained in forging and will guide us in design.更多还原