小直径铣刀铣削淬硬钢切入过程的动力学仿真研究

小直径铣刀是硬铣方式加工复杂型面淬硬模具必不町少的刀具之一，但其切人过程的崩刃、断刀现象非常突出。文中采用动力学仿真软件ADAMS，对小直径铣刀在不同切削参数条件下的切人过程进行仿真分析，以确定小直径铣刀切人过程的载荷、运动形式；然后根据仿真分析的载荷结果，用有限元分析软件ANSYS确定不同切削参数下，铣刀切人过程对刀刃的应力、变形影响，为寻求合理的切人条件、减少刀具破损和提高加工效率提供参考。     

直齿圆柱木工铣刀铣削切入过程动力学仿真分析

木材的各向异性和切削的高速性易使刀具在切削过程中出现断刀和崩刃等现象,尤其在切入工件时使刀具承受很大的冲击。应用ADAMS软件对直齿圆柱木工铣刀铣削木材的切入过程进行动力学仿真,以确定不同转速下铣刀的受载情况;然后根据仿真分析的结果,运用ANSYS软件分析铣刀受载时的内部应力,为物理试验分析提供参考和对照。     

三维复杂槽型铣刀片切入过程应力状态的研究

以哈尔滨理工大学开发的波形刃铣刀片（前刀面为波形曲面）为例,针对刀具切入破损问题,确定了切入瞬问冲击载荷的分布与作用力方向;应用弹性力学方法,对三维复杂槽型铣刀片进行了应力状态分析,并讨论了其应力分布规律。理论分析结果与铣刀片应力场分析结果吻合较好。研究结果为解决自动化生产中刀具破损问题及槽型优化技术研究打下了理论基础。     

基于力-热耦合的三面刃铣刀三维铣削仿真分析

三面刃铣刀是一种广泛用于铣削金属、非金属以及难加工材料的沟槽面和台阶面的标准刀具。本文采用三维拟实的三面刃铣刀模拟铣削加工过程,得出铣刀应力与其工艺参数的关系,以此分析铣刀的破损。首先,考虑到铣削过程中温度场对刀具破损的重要影响,建立并实现了基于瞬态温度-位移耦合的综合力-热应力分析,实现对铣刀刀刃易破损部位的预测。再通过多次仿真试验,得到了刀尖切出应力随铣削参数的变化趋势,并据此给出提高铣刀寿命的建议。最后通过不同切削参数组合下工件表面变形量的有限元预测值与试验对照,验证了模型的真实可靠性。     

基于ADAMS的小直径铣刀铣削淬硬钢斜向切入方式的仿真研究

小直径铣刀是硬铣方式加工复杂型面淬硬模具必不可少的刀具之一,但其切入过程的崩刃、断刀现象非常突出.采用仿真软件ADAMS,对小直径铣刀在不同切入方式进行仿真,以确定小直径铣刀切入过程的载荷、切入过程对刀刃的应力,变形影响.     

硬质合金铣刀片粘结破损的研究

针对铣削难加工材料时刀具粘结破损问题,进行了用平刀片和自主研发的复杂槽型铣刀片切削3Cr1Mo1／4V高温耐热钢的测温测力试验,同时采用高速摄影观察了铣刀片切入切出时粘结切屑脱落过程,应用有限元法分析了粘结破损时温度场和应力场耦舍后的等效合成应力。理论和试验数据分析结果表明,粘结破损的主要原因是工件和刀具材料的亲合力、铣刀片的等效合成应力大于硬质舍金的强度,改变铣刀片的槽型是提高抗粘结破损的有效方法。为三雏复杂槽型铣刀片槽型的优化和重构技术提供了理论依据和试验数据。     

硬质合金端铣刀的破损分析

铣削过程中,针对硬质合金端铣刀的破损形式采取相应措施,根据端铣削的最佳切削条件选择合理的工艺参数,可以有效地提高刀具寿命。     

四刃平头铣刀铣削Ti-6Al-4V钛合金参数优化设计及实验研究

为解决四刃平头铣刀铣削钛合金材料时切削力大、切削温度高等问题,利用AdvantEdge FEM仿真软件对四刃平头铣刀进行铣削仿真分析,从刀具应力分布、切屑形貌的方向优化刀具参数,将最佳刀具参数应用于切削参数仿真中,获得铣削Ti-6Al-4V材料的最佳切削参数,并利用试验进行验证。研究表明：基于刀具应力分布以及切屑卷曲状态获得了最优刀具参数;通过不同切削参数的铣削仿真试验获得了最小切削力参数以及最低切削温度参数,并通过试验验证了仿真有效性,为高效铣削Ti-6Al-4V材料提供有价值的理论参考。     

基于ABAUQS仿真的涂层刀具切削奥氏体不锈钢刀具破损机理研究

利用ABAQUS软件对切削过程进行仿真,探究了涂层刀具切削奥氏体不锈钢时刀具的磨损机理,并结合实际切削试验进行对比。仿真结果表明,切削过程中刀尖附近所受应力最大,且随着切削速度的增加,刀尖处应力值急剧增大,这与实际切削过程中刀具破损形态是刀尖破损相吻合;同时,随着切削速度的增加,刀具出现刀尖破损的时间缩短,这也间接验证了仿真中刀尖应力值与切削速度呈正相关。上述结论验证了利用ABAUQS软件对涂层刀具切削奥氏体不锈钢过程进行仿真是合理可行的。     

耐热钢加工刀具粘结破损数学模型的研究

针对哈尔滨理工大学开发的三维复杂槽型波形刃铣刀片和平前刀面铣刀片,通过对耐热钢的面铣加工进行刀片粘结破损数学模型的研究.首先,进行铣刀片切削温度实验,对铣刀片粘结破损机理进行分析;其次,通过实验揭示不同铣刀片粘结破损失效形式的差异;在粘结破损实验的基础上,建立铣削温度与前刀面最大粘结破损深度之间的数学模型,分析铣削温度对刀具粘结破损的影响规律.研究成果为解决自动化生产中刀具破损这一关键技术问题打下理论与试验基础.     

基于UG的小直径立铣刀应力场有限元分析

为了提高加工精度,对小直径立铣刀的应力场进行了有限元分析。通过铣削力试验,对不同切削参数下立铣刀的铣削力进行动态采集,利用UG建模模块进行立铣刀实体建模,根据铣削力试验结果给出边界条件,在立铣刀有限元模型上加载载荷,利用UG有限元分析模块获得了立铣刀切削过程中切入、切出的瞬时应力场云图,显示了切削中立铣刀应力场的变化规律。     

断续车削切入类型分析

以2Cr13淬硬制动盘的断续车削加工为例,基于M.Kronenberg的断续铣削切入类型模型,提出了盘类零件断续车削的切入类型及判别公式,并分析了在淬硬材料的断续车削中,不同的切入方式、刀具角度和刃形、切削参数对刀具寿命的影响。     

基于UG的立铣刀铣削力的有限元分析

为提高加工精度,对立铣刀的应力场进行了有限元分析。通过铣削力试验,对不同切削参数下立铣刀的铣削力进行动态采集,利用UG中的建模模块进行立铣刀实体建模,根据切削力实验结果给出了边界条件,在立铣刀有限元模型上进行加载,利用UG有限元分析模块,获得了立铣刀切削过程中切入、切出的瞬时应力场云图,显示了切削中铣刀片应力场的变化规律。     

Multidisciplinary design optimization of a milling cutter for high-speed milling of stainless steel

The milling cutter’s fracture strength is more important than its chemical stability and thermal conductivity in high-speed milling. The multidisciplinary design optimization (MDO) method is employed to optimize the fracture-resistant performance of a milling cutter in this work. An experimental study on high-speed milling of the martensitic stainless steel 0Cr13Ni4Mo is conducted. The cutting forces and cutting temperature in the milling process are measured to provide initial data for the structural optimization of the milling cutter. The mathematical models of cutting force and cutting temperature are studied. Considering that the induced stress in the milling cutter is generated by thermomechanical coupling, the thermoelastic–plastic governing equation in the milling process is introduced in this work. The sensitivity of the structural parameters to the maximum equivalent stress of the milling cutter is calculated, and the structural parameters that have the greatest effects on the maximum equivalent stress are determined as design variables for the cutters’ optimization. The MDO procedure for the cutter’s optimization consists of updating of solid model, finite element analysis of thermomechanical coupling, postprocessing, and optimization algorithm. The MDO results show that the optimized milling cutter has a better fracture-resistant performance than the initial one. The maximum deformation, overall equivalent stress, and deformation are decreased.     

Modeling of residual stresses in milling

A model to predict residual stresses produced from milling is presented. It uses process conditions as inputs and predicts surface and subsurface residual stress profiles due to milling. The model formulation incorporates cutting force and cutting temperature predictions and utilizes those parameters to define the thermomechanical loading experienced by the workpiece. Model predictions are compared with published experimental data for both cutting forces and residual stress profiles. The results show that the model performs well in predicting residual stress trends for various milling conditions. Residual stress magnitudes as well as profiles are well predicted with the modeling approach.     

Milling Force Model for Aviation Aluminum Alloy:Academic Insight and Perspective Analysis

Aluminum alloy is the main structural material of aircraft,launch vehicle,spaceship,and space station and is pro-cessed by milling.However,tool wear and vibration are the bottlenecks in the milling process of aviation aluminum alloy.The machining accuracy and surface quality of aluminum alloy milling depend on the cutting parameters,material mechanical properties,machine tools,and other parameters.In particular,milling force is the crucial factor to determine material removal and workpiece surface integrity.However,establishing the prediction model of milling force is important and difficult because milling force is the result of multiparameter coupling of process system.The research progress of cutting force model is reviewed from three modeling methods:empirical model,finite element simulation,and instantaneous milling force model.The problems of cutting force modeling are also determined.In view of these problems,the future work direction is proposed in the following four aspects:(1)high-speed milling is adopted for the thin-walled structure of large aviation with large cutting depth,which easily produces high residual stress.The residual stress should be analyzed under this particular condition.(2)Multiple factors(e.g.,eccentric swing milling parameters,lubrication conditions,tools,tool and workpiece deformation,and size effect)should be consid-ered comprehensively when modeling instantaneous milling forces,especially for micro milling and complex surface machining.(3)The database of milling force model,including the corresponding workpiece materials,working condi-tion,cutting tools(geometric figures and coatings),and other parameters,should be established.(4)The effect of chatter on the prediction accuracy of milling force cannot be ignored in thin-walled workpiece milling.(5)The cutting force of aviation aluminum alloy milling under the condition of minimum quantity lubrication(mql)and nanofluid mql should be predicted.     

高温合金蜂窝芯高速铣削材料去除机理与损伤行为

高温合金蜂窝芯材料具有高比刚度、轻质和能量吸收特性好等优异性能,被视为下一代高超声速飞行器热防护结构极具潜力的材料。高速铣削是高温合金蜂窝芯零件成型过程中重要的减材制造工艺,在蜂窝芯材料高速铣削时,蜂窝芯材料面内刚度低且高温合金塑性好,较小的切削力就会使蜂窝壁产生较大的塑性变形,导致蜂窝芯加工精度较低、加工损伤难以控制,对后续焊接、装配等工序产生不利影响。基于有限元仿真对蜂窝壁切削材料去除机理进行了深入研究,探索了铣削参数、刀具类型和铣削方式对铣削过程中铣削力和加工损伤的影响。研究结果表明,蜂窝壁切入角是影响蜂窝芯材料切削加工过程中瞬时应力分布和成屑机理的关键性因素。得到了铣削参数、刀具类型和铣削方式对高温合金蜂窝芯加工过程中加工损伤的影响规律。对于铣削参数,过大的进给量会导致芯格变形等加工损伤,降低切削速度会提高微小毛刺等加工损伤发生的频率;本文采用的三种刀具的对比结果表明,立式铣刀加工质量最好。插铣方式会产生明显的轴向冲击,而侧铣方式可以有效避免轴向冲击。研究成果为高温合金蜂窝芯低损伤高性能加工提供了理论依据和工艺技术储备。     

High-speed milling of CFRP composites: a progressive damage model of cutting force

Three-dimensional Hashin failure criterion and material stiffness degradation model were compiled by VUMAT subroutine. The Abaqus/Explicit solver was performed to establish progressive damage model of cutting force for CFRP high-speed milling, and high-speed milling experiments with different cutting parameters were carried out. Further, the impact mechanism of fiber cutting angle and cutting parameters on cutting force, stress, and material failure during milling was explored, and the material removal mechanism in high-speed milling of CFRP was revealed. The results show that the error between the experimental and simulated of cutting forces is less than 5%, which indicates that the progressive damage model is feasible. The fiber cutting angle has significant influence on cutting force and stress in cutting process, and the cutting direction has a significant influence on cutting force. In addition, cutting parameters play a critical role in cutting force, and the feed per tooth is the most significant factor affecting the cutting force. Simultaneously, the progressive damage model predicts that the shear failure of materials mainly concentrates in the cutting area and extends along the feed direction. Finally, the material removal mechanism of CFRP in high-speed milling was revealed combining cutting force experiment.     

不等距立铣刀切削力模型的建立及试验分析

在特定铣削条件下,建立了多齿不等距铣刀的切削力模型,并通过正交试验验证所建的切削力模型;通过分析不同的切削参数对切削力系数的影响,综合确定了在小切削宽度铣削过程中合理选用切削参数的基本原则。