汽车模具小曲率面宽行加工技术研究及其刀具开发

发布时间：2018-07-04 22:44

本文选题：小曲率面 + 宽行加工　；参考：《哈尔滨理工大学》2015年硕士论文

【摘要】：汽车覆盖件模具的数控加工效率直接影响了汽车生产与换型周期，其材料多为Cr12MoV和7CrSiMnMoV，属于典型高强度、高硬度材料。本文以汽车覆盖件模具中小曲率面为研究对象，进行了以增加有效切削带宽为目标的宽行加工技术的相关研究，具体如下： 1.为有效分析刀具的铣削性能，提出以刀具单次独立切入工件的有效切削带宽来代替加工带宽。基于几何切触关系，分别分析了环形刀与球头刀与曲面刀触点处的切削速度，并提出基于刀具切入工件部分在刀触点切平面内的投影，建立三轴铣削条件下有效切削带宽与刀具、曲面坡度、切深、进给方向等参数间的数学模型，为环形刀在三轴加工中的刀路优化提供依据。 2.基于环形刀的刀具路径高度变化原则，分别对两类特殊型面进行了刀路轨迹规划，并通过实验和仿真证明了基于高度变化走刀方法的优势。分析了环形刀三轴加工平坦类小曲率凹曲面的曲率干涉问题，并提出了使用高进给铣刀代替环形刀完成平坦小曲率凹曲面的半精加工，以此减小欠切量，，并提出了相应刀路轨迹规划方案。 3.针对复杂型腔类零件设计了一种二次开粗与半精加工专用的新型铣刀，其避免了球头刀刀尖速度为零的缺陷，而与环形刀相比，其能明显减小欠切量；提供了可转位刀具和整体硬质合金刀具的设计方案，并磨制出整体硬质合金的新型刀具，进行了新型刀具实际加工效果的验证实验。 4.进行了典型汽车模具小曲率面的宽行加工实验验证，分别针对小曲率凸凹曲面制定了相应的工艺规划流程。实验结果表明，与普通球头刀加工方法相比使用宽行加工技术方法能够提高加工效率25%以上。
[Abstract]:The NC machining efficiency of automobile panel die has a direct effect on the cycle of automobile production and change. The materials are mostly Cr12MoV and 7CrSiMnMoV, which are typical high strength and high hardness materials. In this paper, the small and medium curvature surface of automobile panel die is taken as the research object, and the related research of the wide line machining technology aiming at increasing the effective cutting bandwidth is carried out. The details are as follows: 1. In order to effectively analyze the milling performance of cutting tools, the effective cutting bandwidth of a single independent cutting tool is proposed to replace the machining bandwidth. Based on the geometric contact relation, the cutting speed at the contact point of the ring cutter and the spherical cutter and the curved tool is analyzed respectively, and the projection of the cutting part of the cutter into the cutter contact plane is proposed. The mathematical model between the effective cutting bandwidth and the parameters such as cutting tool, curved surface slope, cutting depth and feed direction under the condition of triaxial milling is established, which provides the basis for optimizing the cutting path of annular cutter in triaxial machining. 2. Based on the principle of tool path height variation of annular cutter, the tool path planning for two kinds of special surfaces is carried out, and the advantages of the method based on height variation are proved by experiment and simulation. In this paper, the problem of curvature interference in triaxial machining of flat concave surfaces with small curvature is analyzed. In order to reduce the undertangent, the high feed milling cutter is used instead of the annular cutter to finish the semi-finishing of flat concave surfaces with small curvature. At the same time, the corresponding path planning scheme is put forward. 3. A new type of milling cutter is designed for complex cavity parts. It avoids the defect that the tip speed of the cutter is zero, and compared with the annular cutter, it can obviously reduce the undercut. The design scheme of the indexable tool and the whole cemented carbide tool is provided, and the new cutting tool of the whole cemented carbide is grinded, and the verification experiment of the actual machining effect of the new type of tool is carried out. 4. The wide line machining experiment of typical small curvature surface of automobile die is carried out, and the corresponding process planning flow is made for the convex and concave surface with small curvature respectively. The experimental results show that the wide line machining method can improve the machining efficiency by more than 25%.
【学位授予单位】：哈尔滨理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U466;TG76

【参考文献】