镍基激光熔覆合金涂层高速铣削切削力试验研究

为研究高速铣削镍基激光熔覆合金涂层切削加工性能,探明高速铣削时铣削参数对切削力的影响规律。以Q690为基材,镍60合金粉末为熔覆材料制备铣削试件。采用硬质合金立铣刀对熔覆合金涂层进行高速铣削试验,利用单因素试验法,研究分析高速铣削下铣削深度、进给速度和主轴转速对镍基熔覆合金切削力的影响规律。结果表明,高速铣削镍基熔覆合金时径向切削力F_x、轴向切削力F_z和主切削力F_y均随铣削深度和进给速度的增大而增大,随主轴转速的增大而减小;三个方向的分力中主切削力F_y最大;三个铣削参数对切削合力F_合的影响显著性为切削深度a_p>进给量v_f>主轴转速s。     

涂层刀具高速铣削高硬度淬硬钢切削力研究

采用四种不同涂层硬质合金铣刀高速铣削四种不同硬度的淬硬钢材料,研究了刀具涂层成分、工件材料硬度以及切削工艺参数(切削速度、每齿进给量、轴向铣削深度和径向铣削深度)对切削力的影响。研究表明：随着切削速度的增大,淬硬钢P20和S136的切削合力影响较小,而对于淬硬钢SKD11和PM60,改变切削速度对切削合力影响显著。随着切削速度的增大,四种不同涂层刀具切削淬硬钢S136产生的切削合力先快速增大后缓慢减小,刀具切削力大小顺序一直保持为TiSiN>CrSiN>AlCrN>TiAlN,其中TiAlN涂层相对于其余三种刀具涂层在降低切削力、减少工件与刀具之间的相互摩擦具有优势。切削参数的变化对切削力的影响与淬硬钢工件硬度的变化存在相互影响,淬硬钢硬度低于HRC55时,切削工艺参数的变化对于切削力的变化影响不明显;而当淬硬钢硬度高于HRC60时,随着切削工艺参数的增大,切削力发生显著变化。     

RuT400切削力预测模型及参数优化

针对蠕墨铸铁RuT400难加工的问题,通过使用硬质合金涂层刀具对RuT400进行高速铣削试验,以实验参数为基础构建了切削力预测模型,结合其切削性能并使用响应面法对切削参数进行优化。实验结果表明:使用硬质合金涂层刀具切削RuT400是可行的,而且刀具价格便宜,加工经济性更好。切削速度、进给速度、切削深度与切削力之间存在显著的线性关系,根据实际加工参数使用切削力预测模型可以对切削力作出精确预测;切削力随着切削深度的增加以严格的线性方式递增;切削用量对切削力影响的显著性顺序为:切削深度进给速度切削速度。一般情况下,较小的切削深度,适当的进给速度和较大的切削速度能获得较低的切削力和良好的加工效率。     

69111铣削加工参数优化研究

针对69111不锈钢材料的难加工性,设计四因素四水平正交切削实验,探索不同工艺参数对69111材料加工的影响规律。以铣削力和表面粗糙度为目标进行工艺参数优化。采用极差分析方法对铣削力数据进行处理,获得不同工艺参数对铣削力影响序列,同时采用非线性回归方法,获得切削力经验公式,为切削力的预测提供理论依据;对表面粗糙度值进行极差分析,获得不同工艺参数对Ra的影响程度,综合工艺参数对切削力和表面粗糙度的影响进行工艺参数优化,为实际生产69111材料高速高效加工提供支持。     

基于ABAQUS的钛合金铣削力的模拟分析

为了研究钛合金在铣削过程中切削力随着切削参数的变化规律,建立了三维斜角切削有限元模型。通过对材料本构模型,刀—屑接触摩擦模型和切屑分离准则等关键环节建模,采用通用有限元求解器ABAQUS/Ex-plicit对钛合金Ti6Al4V的斜角切削过程进行了模拟,获得了切削速度v、切削深度ap和每齿进给量fz对切削力的变化趋势及影响程度。模拟结果表明:切削力随着切削深度ap和每齿进给量fz的增大而增大,而随着切削速度增大切削力波动很小。切削深度对切削力的影响最大,进给量次之,切削速度对切削力的影响最小。该模型可以为切削参数的合理选择提供参考。     

TC11钛合金插铣工艺切削参数选择方法研究

为了优化TC11钛合金插铣加工的切削参数,采用三因素四水平正交实验法进行了插铣实验,建立了插铣过程中切削力和切削温度的经验公式,分析了插铣参数对切削力及切削参数的影响规律。基于此规律以及刀具许用挠度,提出了铣削速度、每齿进给量和铣削深度的选择方法。结果表明:铣削深度对切削力影响最大,而铣削速度对切削温度影响最大;插铣参数选取原则是在刀具材料允许下取较大铣削速度,适中的每齿进给量,最后根据刀具挠度选择合适的铣削深度。最后在根据此原则选择的插铣切削参数条件下,材料切除率达到了25.1 cm3/min。     

铣削加工中切削参数对切削力的影响

切削力是影响零件加工质量和刀具使用寿命的重要因素,而切削力的大小又是和切削参数息息相关的,因此,研究铣削加工中切削参数各因素(切宽、切深和每齿进给量)对切削力的影响有着非常重要的意义.文中通过设计一系列的切削实验,对铣削加工过程中,影响切削力的切削参数各因素进行了分析,从而得出其中的普遍性规律,为铣削加工中切削参数的选...     

TC4铣削中超临界CO2混合油膜附水滴的冷却润滑性能

在干切削、超临界CO2（scCO2）以及scCO2与油膜附水滴(OoW)混合三种绿色切削方式下对钛合金进行了铣削试验。通过单因素试验分析了铣削参数和冷却润滑方式对切削力、切削温度、表面粗糙度的影响规律,研究了scCO2与OoW混合冷却方式在钛合金铣削中的冷却润滑性能。结果表明,三种冷却润滑方式下,随着切削速度、每齿进给量和径向切宽的增大,切削力和切削温度均呈现增大趋势;当切削速度进一步增大时,依据高速切削加工理论,切削力和温度有增长变缓和下降的趋势;不同加工参数下,相比干切削和scCO2,scCO2与微量油膜附水滴混合冷却方式能有效减小切削力和降低切削温度,并获得良好的加工表面,具有良好的冷却润滑性能。     

侧铣削参数对TC4钛合金表面粗糙度及材料去除率的影响

侧铣采用铣刀侧刃对工件进行铣削,是一种重要的数控加工方式,常用于直纹面零件.针对TC4钛合金的侧铣削加工,开展了主轴转速、进给速度、切削深度、切削宽度的四因素三水平正交试验,分析侧铣削参数对切削力、表面粗糙度及材料去除率的影响.试验结果表明,切削深度和主轴转速对切削力和表面粗糙度的影响较大,进给速度次之,切削宽度最小.切削深度和切削宽度的增大会显著提高材料去除率,在主轴转速为600r/min,进给速度为220mm/min,切削深度为5mm,切削宽度为0.4mm时,侧铣TC4钛合金的表面粗糙度质量较好且材料去除率较大.     

铣削高强钢时高效余量去除的切削力研究

采用涂层硬质合金刀具对AF1410超高强度钢进行高效余量去除铣削实验,分析研究了高效余量去除铣削高强钢时切削参数及冷却条件对切削力的影响。结果表明,在干切削条件下,切削速度对切削力的影响较复杂;湿切削时,切削速度对切削力的影响较稳定;两种条件下,轴向力受切削用量影响较小。在干式切削条件下,切削深度的增加对径向力和切向力影响显著,切削力随每齿进给量的增加而增大,每齿进给量增加到0.08mm/z时,切削力有下降趋势;在实验参数范围内,湿式及干式切削均表现为径向力>切向力>轴向力,但采用干式切削且切削深度大于2mm后,切向力大于径向力。     

球头刀铣削淬硬钢倾斜表面切削力试验研究

采用正交试验方法,使用PCBN涂层硬质合金球头铣刀,对不同铣削参数下的52HRC淬硬钢Cr12MoV倾斜表面进行了铣削试验。研究了各工艺参数对切削力的影响规律。试验结果表明:三向力中,Fz远大于Fx和Fy的切削分力,Fz为主铣削力;切削深度对主铣削力的影响大于进给速度、工件倾角和主轴转速对其的影响;工件倾角16.7°,主轴转速6000r/min,进给速度800mm/min,切削深度0.1mm为优选工艺条件。同时,对比试验表明,采用顺铣方式能有效减小切削力,改善铣削稳定性。本文研究结果对淬硬钢Cr12MoV铣削工艺参数的优化具有一定的参考价值。     

汽车覆盖件拼接模具硬态铣削过程的动态特性

针对汽车覆盖件拼接模具铣削过程铣削力及振动信号测试失真问题,运用经验模态分解(empirical mode decomposition,简称EMD)结合小波阈值降噪原理,对铣削力及振动信号进行降噪处理。对降噪后的振动信号进行时频域分析,研究了不同切削参数、切削进给方向对铣削拼接模具过程动态特性的影响,得到铣削方向由硬度大材料切向硬度小材料,走刀方向与拼接缝成30°夹角时铣削力突变值较小的结论。发现x,y,z方向的切削分力及振动幅值的突变值与轴向切深及进给速度呈现正相关,与切削速度是非线性关系的特性。该研究结果为汽车覆盖件拼接模具硬态铣削的工艺优化提供了理论支持。     

GH4169插铣参数对切削力的影响规律研究

为了优化高温合金GH4169插铣加工过程中的切削参数,采用正交试验法进行高温合金GH4169的铣削试验。基于试验法建立了切削力与切削参数之间的经验公式,分析了各切削参数对切削力的影响规律。运用方差分析法检验了经验公式的显著性。结果表明:F_x、F_y、F_z都随着切削速度V_c、每齿进给量f_z、径向切深a_e的增大而增大;三个方向的切削力受径向切深a_e的影响最大,其次是切削速度V_c,每齿进给量f_z的影响最小,且Z方向切削力F_z大于X、Y方向切削力F_x、F_y。     

陶瓷刀具高速铣削4Cr13不锈钢铣削力试验研究

采用单因素试验,分析了切削速度vc、每齿进给量fz和切削深度ap对铣削力的影响规律,结果表明:随着切削速度vc的增大,铣削力减少;随着每齿进给量fz和切削深度ap增大,铣削力增大。同时,设计了4Cr13不锈钢正交试验方案,基于概率统计和回归分析原理,建立了4Cr13不锈钢高速铣削的铣削力模型,对建立的铣削力模型进行了显著性检验,检验结果表明所建立的回归方程呈高度显著检验状态,并对其进行了验证,结果表明该模型与实际情况拟合得较好,故可用其来预测和控制铣削力。     

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.     

Effect of machining parameters on the milling process of 2.5D C/SiC ceramic matrix composites

Abstract

The C/SiC ceramic matrix composites are widely used for high-value components in the nuclear, aerospace and aircraft industries. The cutting mechanism of machining C/SiC ceramic matrix composites is one of the most challenging problems in composites application. Therefore, the effects of machining parameters on the machinability of milling 2.5D C/SiC ceramic matrix composites is are investigated in this article. The related milling experiments has been carried out based on the C/SiC ceramic matrix composites fixed in two different machining directions. For two different machining directions, the influences of spindle speed, feed rate and depth of cut on cutting forces and surface roughness are studied, and the chip formation mechanism is discussed further. It can be seen from the experiment results that the measured cutting forces of the machining direction B are greater than those of the in machining direction A under the same machining conditions. The machining parameters, which include spindle speed, feed rate, depth of cut and machining direction, have an important influence on the cutting force and surface roughness. This research provides an important guidance for improving the machining efficiency, controlling and optimizing the machined surface quality of C/SiC ceramic matrix composites in the milling process.     

超声振动铣削加工参数对切削力的影响

为了改善传统铣削钛合金的加工条件,研究了进给方向超声振动辅助铣削对切削力的影响。定值计算了不同振动频率、振幅、铣削速度时的净切削时间比,建立了对工件施加超声振动的铣削加工三维有限元模型,根据仿真结果讨论了加工参数对进给方向切削力瞬时值的影响,并结合净切削时间比分析了加工参数对三个方向切削力平均值的影响。研究表明:施加超声振动后切削力明显减小;振动频率小于40kHz和振幅小于30μm时切削力平均值同净切削时间比变化趋势一致,当频率或振幅超过上述值时,刀具、工件间的摩擦力对切削力平均值的影响显著。     

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.     

基于主轴电流的铣削力间接监测方法

实时准确地监测铣削状态对于提高加工质量与加工效率具有重要意义,切削力作为重要的加工状态监测对象,因其监测设备昂贵且安装不便而受到限制,为此提出一种考虑刀具磨损的基于主轴电流的铣削力监测方法.首先基于切削微元理论建立了考虑后刀面磨损的铣削力模型,并通过铣削实验进行铣削力模型系数标定;然后对主轴电流与铣削力的关系进行理论建...     

Extension of process damping to milling with low radial immersion

This paper investigates the stabilizing effect of process damping at low cutting speeds for regenerative machine tool vibrations of milling processes. The process damping is induced by a velocity-dependent cutting force model, which takes into account that the actual cutting velocity is different from the nominal one during machine tool vibrations. The chip thickness and the cutting force are calculated according to the direction of the actual cutting velocity. This results in an additional damping term in the governing delay-differential equation, which is time-periodic for milling and inversely proportional to the cutting speed. In the literature, this term is often assumed to be constant and is considered to improve stability properties at low spindle speeds. In this paper, it is shown that the velocity-dependent cutting force model captures the improvement in the low-speed stability only for turning operations and milling with large radial immersion, while it results in a negative process damping term for low-immersion milling. Consequently, an extended process damping model is needed to explain the low-speed stability improvement for low radial immersion milling.