【作者】 邵子东；

【导师】 贾秀杰； 孙杰；

【作者基本信息】 山东大学 ， 机械制造及其自动化， 2007， 硕士

【摘要】 高速加工技术正成为切削加工的主流,而高速刀具是实现高速加工的关键技术之一。螺旋立铣刀因其切削性能好,加工表面质量高,在高速加工特别是复杂曲面、自由曲面的高速加工中应用非常广泛,更是高速加工航空铝合金整体结构件不可或缺的工具。但由于螺旋立铣刀结构形状极其复杂,给设计和制造带来困难。首先,本文在对整体式圆柱立铣刀按头型进行分类的基础上,从几何角度的定义出发,对其几何参数进行数学描述,建立了立铣刀的刃形线和截面线的数学方程式。通过三维CAD软件UG强大的表达式功能以及扫描、布尔运算、特征合成等技巧,在UG环境下实现了整体式圆柱立铣刀通用模型的结构设计。第二,切削力是切削加工过程中主要的物理现象之一。切削力的变化不仅影响切削热的产生、分布而且影响刀具磨损、使用寿命;切削力还是刀具设计不可缺少的依据。通常预测切削力要根据经验公式,但在高速铣削特别是铝合金材料研究中,没有完善的理论可供借鉴。所以,研究硬质合金立铣刀高速铣削铝合金的铣削力,试验是最可靠的方法。本文采用正交试验方法研究高速铣削过程中多因素对铣削力的影响,推导了四因素、四水平回归正交试验法的数学模型,该模型的建立为相关领域的试验研究工作提供一定支持。第三,通过试验研究铣刀的应用情况不仅十分困难而且费力费财,在一定程度上可以采用计算机仿真的方法辅助研究。本文在有限元软件ABAQUS环境下对铣刀受力以及动态性能进行模拟,获得铣刀的应力状况以及铣刀加工中的阶次和固有频率。该结果可以为铣刀在实际加工中合理选择切削用量以及为立铣刀结构设计中刀柄长、切削刃、刀背、螺旋角等参数尺寸的确定提供帮助。第四,高速加工中,切削力、切削热和机床振动等被广泛研究,而切屑研究相对较少。本文针对立铣刀高速铣削的特点,对切屑的成形进行了研究。根据理论分析在UG环境下对切屑进行了绘制,其形状与实际切屑基本吻合,证明了研究方法的可靠性。通过切屑的研究反馈设计过程,对立铣刀的结构设计提供支持。全文以立铣刀的设计为主线,各个环节包括试验和仿真研究都为设计过程服务,使整个过程如同一个完整的闭环系统。最后通过试验对本论文研究结论进行了验证,从而说明本论文研究的思路、方法是可行的,研究结果也是可靠的。更多还原

【Abstract】 High-speed machining (HSM) has become the main trend in the machining field, high-speed milling cutter is one of the crucial technologies to achieve high-speed machining. As a result of its many advantage as good cutting property, excellent machining, surface quality and so on, helical end milling cutter is applied in high-speed machining widely, especially in complicated surface, and large-scale integrated part in aircraft. It is very difficult to design and manufacture helical end milling cutter because its intricate geometry configuration.Firstly, the end milling cutters are classified by their head figure, on the basis of their sort, the geometry parameters are depicted, the curve expressions of edges and sections are founded. By the powerful expression function and some skills as sweep, boolean of UG, the proper geometry model of end milling cutter is achieved. Three-dimensional model can be created into planar engineering drawing and guided into finite element software ABAQUS to actualize analysis, Base on the property of cutter in HSM as force and vibration, refer to classics literature and handbook of overseas, contacting material property, establish proper configuration parameters adapt to HSM.Secondly, cutting force is one of the important physical in machining. The changing of cutting force affects appearing and distributing of cutting heat and wear of cutting tools, and it is the indispensability condition of the design of cutting tools. It is usually that the experiential formula is the basis to forecast cutting force, but in the high-speed machining especially in aluminium alloy machining, there are no perfect theory. So to study cutting force of machining aluminium alloy by carbide end milling cutter, experiment is the most dependable method. The regression-orthogonal experimental method is applied to study the effect of cutting force by many factors. The mathematics model was deduced of four factors and four standards. The models were not only used in this thesis, but also can be used in similar experimental study for interrelated fields.Thirdly, milling cutters were machined in the machining tools, so the property of cutters has relation with machine tools and fixture. To study its property by experiment is wasteful and unpractical. In the environment of Abaqus, the load of cutter and its dynamic property were simulated, The results of loading condition and fixed frequency are achieved. These conclusions can give the help of choosing cutting parameters and configuration design of cutter as handle, edge, helical angle, width of blade.Fourthly, in high-speed machining, cutting force, cutting heat and vibration of machining tools are studied usually, but the chip is studied little. Aim at the character of high-speed machining, the figuration of chip was studied. By the theory, the figure of chip was drawed in UG, theory results were agree with experimental results. The study of chip can be feed back to the design of cutters. The method is dependable.The design of cutters was the key point in this paper, any tache as experiment and simulation are service. It can be looked as a closed loop. The conclusions of paper were validated by compared analysis example distortion with the real part distortion. The results from the test examples have demonstrated the feasibility and veracity of the proposed methods.更多还原