正交切削加工温度场的有限元仿真分析

本文简述了切削加工切削热的产生于传导,基于有限元仿真技术分析了正交切削加工过程的温度场分布,并对结果进行了后置处理与分析,结果表明有限元仿真技术的分析结果对研究切削加工过程有较好的辅助作用。     

钝圆刀刃切削的有限元模拟

利用商业有限元分析软件Marc对考虑切削刃钝圆半径的切削加工过程进行了有限元模拟。分析了切削刃钝圆半径在切削加工过程中对切削力和切削温度的影响     

基于有限元法的二维正交切削刀具应力分析

运用有限元方法对二维正交切削加工刀具内部应力进行模拟分析。基于刚塑性有限元方法建立了切削加工过程仿真模型,通过模拟获得了切削加工过程中刀具应力的分布和变化情况。通过对不同切削工艺参数条件下的切削过程进行模拟,分析了刀具几何参数以及切削用量对切削加工过程中刀具应力的影响,为正确选择刀具及切削参数提供了参考。     

刀具前角对切削过程的影响

运用商业非线性有限元软件DEFORM对金属切削加工过程进行模拟,分析了不同刀具前角、钝圆半径在切削加工过程中对切削温度,切削应力的影响,为刀具设计提供了依据。     

刀具几何参数对切削加工过程的影响

运用商业非线性有限元软件MARC,对金属切削加工过程进行了弹塑性热力耦合模拟,分析了不同刀具前角、切削刃钝圆半径在切削加工过程中对切削力、切削温度、工件残余应力及残余变形量的影响。     

切削深度对超精密切削过程影响的有限元分析

基于大变形有限元理论和更新的拉格朗日方程式 ,建立了热耦合的平面应变正交切削有限元仿真模型。采用通用的商业非线性有限元软件 ,对无氧铜超精密切削加工过程进行了仿真 ,研究超精密切削过程中切削深度对切削力、残余应力、等效应力、等效应变和切削温度的影响。通过对超精密切削有限元仿真结果的分析 ,可以优选出合理的切削参数。     

金属切削加工过程的有限元数值模拟

运用有限元方法对切削过程进行数值模拟,分析不同切削速度在切削加工过程中对切削温度及切削力的影响,从而有助于深入了解加工过程,合理选择加工工艺参数。     

汽车覆盖件模具高速切削参数优化研究

深入研究切削加工有限元模拟技术并将该技术在汽车覆盖件模具高速切削加工过程中进行应用。建立了高速切削加工三维有限元模型,研究了热力耦合有限元控制方程、材料本构模型等关键技术。进一步对汽车覆盖件模具高速切削加工过程进行了模拟和分析。研究结果表明:以不同的生产指标为优化目标,获得的最优高速切削加工参数不同;以加工效率、刀具寿命和加工质量等综合最优为目标,最佳切削加工参数为主轴转速为11000r/min,每齿进给量为0.4mm,铣削深度为0.25mm,铣削宽度为0.4mm。     

GH4169高温合金球头铣刀铣削有限元仿真分析

GH4169高温合金在切削加工过程中通常会产生较大的切削力和较高的切削温度,进而难以控制加工表面完整性。借助ABAQUS有限元分析软件中的Johnson-Cook热力耦合模型建立球头铣刀简化模型,对GH4169高温合金的铣削加工过程进行三维有限元模拟仿真,研究GH4169高温合金材料在球铣削过程中的切削力、切削温度、等效塑性应变和应变率的变化与分布规律,并对比分析仿真结果与试验结果的差异。研究结果表明,仿真模型的预测结果与试验测量结果有较好的一致性,所构建的铣削有限元仿真模型为球头铣刀的铣削加工提供了可参考的切削要素。     

合金铸铁高速切削的有限元模型

提出了进行高速切削有限元模拟的过程,研究了刀屑间的摩擦和热传递等关键技术,通过高速压缩试验,获得了钼铬铸铁力学性能,建立了钼铬铸铁高速切削的有限元模型。在通过切削力试验对钼铬铸铁高速切削加工过程中的切削温度、应力分布和切屑的形成等进行了验证。分析结果表明该有限元模型可以用来进行钼铬铸铁的高速切削过程仿真,为进一步的研究提供了基础。     

MODELING THE PHYSICS OF METAL CUTTING IN HIGH-SPEED MACHINING

Physical modeling of metal cutting was carried out to provide an understanding and prediction of machining process details. The models are based on finite element analysis (FEA), using a Lagrangian formulation with explicit dynamics. Requirements for material constitutive models are discussed in the context of high-speed machining. Model results address metal cutting characteristics such as segmented chip formation, dynamic cutting forces, unconstrained plastic flow of material during chip formation, and thermomechanical environments of the work-piece and the cutting tool. Examples are presented for aerospace aluminum and titanium alloys. The results are suited for analysis of key process issues of cutting tool performance, including tool geometry, tool sharpness, workpiece material buildup, and tool wear.     

MODELING THE PHYSICS OF METAL CUTTING IN HIGH-SPEED MACHINING

ABSTRACT

Physical modeling of metal cutting was carried out to provide an understanding and prediction of machining process details. The models are based on finite element analysis (FEA), using a Lagrangian formulation with explicit dynamics. Requirements for material constitutive models are discussed in the context of high-speed machining. Model results address metal cutting characteristics such as segmented chip formation, dynamic cutting forces, unconstrained plastic flow of material during chip formation, and thermomechanical environments of the work-piece and the cutting tool. Examples are presented for aerospace aluminum and titanium alloys. The results are suited for analysis of key process issues of cutting tool performance, including tool geometry, tool sharpness, workpiece material buildup, and tool wear.     

Material removal and chip formation mechanisms of UHC-steel during grinding

Laser shock forming (LSF) is a sheet plastic forming technology, which employs laser-induced shock waves to make sheet metal duplicate a desired shape of the mold. In this paper, a finite element analysis (FEA) model was developed to simulate dynamic forming process with the commercial finite element code ABAQUS/Explicit, and a series of dynamic deformation behaviors of the metal sheet shaped into conical cup at the end of different periods of time were displayed and discussed in detail. The springback of conical cup and the distribution of residual stress were analyzed with ABAQUS/Standard. All these investigations could provide insight into the physics process of the ultra-fast deformation. The LSF experiment was further conducted to verify the results predicted by FEA. The experiment results are well consistent with the numerical predicted data, which validates the FEA model. It indicates that FEA can be used to simulate the forming process and optimize its parameters.     

不同条件下的正交切削温度场的数值分析

建立正交切削加工过程中的传热数学模型,基于Lagrange描述法和有限元法对正交切削的温度场进行数值计算,应用Deform有限元分析软件对不同加工材料、不同切削前角以及不同切削参数下的切削过程进行仿真,得出影响温度场的变化规律.研究结果表明,切削过程的热量主要由材料的塑性变形和切屑与刀具的摩擦产生的,在不改变材料属性的前提下,通过调整切削参数和刀具的形状来降低切削过程的温度,并给出具体刀具前角大小的温度影响分布曲线,为切削加工过程的优化提供参考依据.     

基于有限元分析的二轴柔性滚弯过程影响因素的研究

利用弹性介质对钣金件进行二轴柔性滚弯成形是一种先进的钣金制造工艺,将弹性介质(聚氨酯橡胶)的冲压优势和传统滚弯原理结合,成为钣金成形领域的一个新的发展方向。本文利用有限元软件MARC建立二轴柔性滚弯过程的有限元分析模型,成功的模拟了板料滚弯成形及回弹的加工过程,对工件滚弯成形过程的主要影响因素进行了分析,给出了压入深度、柔性层厚度、刚性滚轴半径、材料性能与回弹后曲率半径的关系。分析结果表明,有限元模拟对滚弯过程的工艺参数选取有着一定的指导意义。     

Modelling the cutting forces in micro-end-milling using a hybrid approach

This paper presents the development of a cutting force model for the micro-end-milling processes under various cutting conditions using a hybrid approach. Firstly, a finite element (FE) model of orthogonal micro-cutting with a round cutting edge is developed for medium-carbon steel. A number of finite element analyses (FEA) are performed at different uncut chip thicknesses and velocities. Based on the FEA results, the cutting force coefficients are extracted through a nonlinear algorithm to establish a relationship with the uncut chip thickness and cutting speed. Then, the cutting force coefficients are integrated into a mechanistic cutting force model, which can predict cutting forces under different cutting conditions. In order to account for the cutting edge effect, an effective rake angle is employed for the determination of the cutting force. A comparison of the prediction and experimental measured cutting forces has shown that the developed method provides accurate results.     

Finite element simulation of machining of Ti-6Al-4V alloy with thermodynamical constitutive equation

Titanium alloys are known as difficult-to-machine materials, especially at higher cutting speeds, due to their several inherent properties such as low thermal conductivity and their high reactivity with cutting tool materials, which present a low thermal conductivity. In this paper, a finite element analysis (FEA) of machining for Ti-6Al-4V is presented. In particular, the thermodynamical constitutive equation in FEA is applied for both workpiece material and tool material. Cutting temperature and tool wear depth are predicted. The comparison between the predicted and experimental cutting temperature and tool wear depth are presented and discussed. The results indicated that a good prediction accuracy of both principal cutting temperature and tool wear depth can be achieved by the method of FEA with thermodynamical constitutive equation.     

金属切削过程有限元仿真关键技术及应考虑的若干问题

华侨大学摘要:有限元仿真是研究金属切削的一门有效而重要的技术。本文介绍在金属切削过程模拟中有限元仿真技术的应用和发展,深入分析和研究工件材料模型、自适应网格划分、切屑分离判别、刀—屑接触面摩擦模型以及刀—屑接触长度确定等五项关键技术;讨论了在实际金属切削过程有限元仿真中的真实性、可操作性、效率等方面应考虑的若干问题。     

地铁盾构刀盘改造的有限元分析

对改造后的地铁盾构刀盘进行有限元分析,利用Solidwork软件对改造刀盘进行模拟仿真,得出刀盘施工状态下的应力云图,为改造后的刀盘能够正常施工提供理论及实验依据.     

单轴柔性滚弯成形的有限元分析研究

利用弹性介质(聚氨酯橡胶)对钣金件进行单轴柔性滚弯成形是一种先进的钣金制造工艺。论文介绍了单轴柔性滚弯的工作原理,同时,将大变形弹塑性有限元引入单轴柔性滚弯成形领域,利用高级非线性有限元软件MSC/MARC,建立了单轴柔性滚弯挤压矩形管成形过程的三维有限元模型,成功模拟了板料滚弯成形及回弹的实际过程,对工件滚弯成形过程的主要影响因素进行了分析,获得了滚轴的压入量、橡胶硬度、滚轴直径与回弹后工件的曲率半径之间的关系曲线。