摩托车齿形链链轮冷挤压成形工艺研究

发布时间：2018-06-19 09:37

本文选题：齿形链链轮 + 冷挤压　；参考：《重庆理工大学》2013年硕士论文

【摘要】：齿形链传动具有传动平稳、噪声低的优点，被广泛地应用到汽车、摩托车的发动机传动装置中。齿形链链轮通常采用铣削加工，工艺复杂，生产效率低，不能满足大批量生产的需要。冷挤压是一种近形成形的加工方法，即生产出的零件基本接近最终零件的要求，具有生产效率高、材料消耗少、表面质量好、金属力学性能强和自动化程度高等优点，尤其在大批量生产中具有其独特的优越性。将冷挤压技术应用于齿形链链轮的生产中，具有广泛的应用前景。摩托车齿形链链轮冷挤压成形的难点在于金属局部流动剧烈，在成形过程中会产生工艺缺陷，零件的成形质量难以保证。因此，通过研究工艺参数对金属流动的影响规律，为工艺方案的制定和工艺参数的选择提供理论依据。本文针对齿形链链轮冷挤压成形过程中产生的齿面裂纹和齿形塌角缺陷展开研究。依据断裂准则，建立起以损伤因子作为裂纹判据的研究方法。运用刚塑性有限元分析软件DEFORM-3D对齿形链链轮的成形过程进行数值模拟，分析了裂纹缺陷产生的原因。通过数值模拟，获得了入模角对齿面裂纹缺陷的影响规律。通过测定模拟成形后挤压件齿顶边缘与凹模模面的距离方法，定量地判断塌角缺陷的程度。通过建立可容速度场，确定了齿形塌角缺陷的影响参数。运用有限元数值模拟的方法，获得了入模角对齿形塌角缺陷的影响规律。在此基础之上，对工艺方案进行优化，提出了合理的成形方案和工艺参数。在上述研究的基础之上，进行齿形链链轮的冷挤压成形工艺试验，验证使用损伤因子判据来研究齿面裂纹缺陷的可行性。
[Abstract]:Toothed chain drive has the advantages of stable transmission and low noise, so it is widely used in the engine transmission of automobile and motorcycle. The gear chain sprocket is usually milling, the process is complex and the production efficiency is low, it can not meet the needs of mass production. Cold extrusion is a kind of near forming processing method, that is, the parts produced are close to the requirements of the final parts, and have the advantages of high production efficiency, less consumption of materials, good surface quality, strong mechanical properties of metals and high degree of automation, etc. Especially in mass production has its unique advantages. Cold extrusion technology is widely used in the production of chain sprocket. The difficulty of cold extrusion forming of the chain sprocket of motorcycle is that the metal flows violently in the process of forming and the forming quality of the parts is difficult to be guaranteed. Therefore, by studying the influence of process parameters on metal flow, the theoretical basis is provided for the formulation of process scheme and the selection of process parameters. In this paper, the crack of tooth surface and the defect of tooth collapse angle produced during cold extrusion of chain sprocket are studied in this paper. According to the fracture criterion, a research method of crack criterion based on damage factor is established. The forming process of chain sprocket with tooth profile was numerically simulated by using rigid plastic finite element analysis software DEFORM-3D, and the causes of crack defects were analyzed. Through numerical simulation, the influence of the angle of entry die on the defect of tooth surface crack is obtained. By measuring the distance between the top edge of the tooth top and the die surface of the extruded parts after simulated forming, the degree of the defect of collapse angle was quantitatively determined. By establishing the admissible velocity field, the influence parameters of tooth collapse angle defect are determined. By means of finite element numerical simulation, the law of the influence of the angle of entry on the defect of tooth collapse angle is obtained. On this basis, the process scheme is optimized, and the reasonable forming scheme and process parameters are put forward. On the basis of the above research, the cold extrusion forming process test of the sprocket with tooth shape chain is carried out to verify the feasibility of using the damage factor criterion to study the crack defect on the tooth surface.
【学位授予单位】：重庆理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TH132.45;TG376.3

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