Inconel625高速车削过程切削力有限元仿真研究

切削力是衡量材料切削加工性能的重要指标。针对航空材料Inconel625可切削性较差的问题,应用有限元仿真软件DEFORM-3D建立硬质合金刀具高速车削Inconel625的三维模型。通过设计正交试验获得切削力仿真数据,根据极差分析,确定切削三要素对切削合力的影响程度:切削深度最大,进给量次之,切削速度最小;应用遗传算法(Genetic Algorithm)建立硬质合金刀具高速车削Inconel625的指数型切削力经验公式,利用拟合优度验证了该公式的可靠性。     

涂层硬质合金刀具切削Inconel718合金的有限元分析

采用Third Wave AdvantEdge切削仿真软件对Inconel 718合金进行车削有限元模拟,通过2D有限元模块分析了单层/多层涂层硬质合金刀具,在不同切削速度下的切削力、进给力和切削温度,以及涂层厚度对切削性能的影响,研究结果对新刀具材料和涂层的设计具有一定指导作用。     

切削Inconel718表面粗糙度的试验研究

利用涂层硬质合金刀具对Inconel 718进行了高速切削试验,对不同切削参数下刀具的切削用量及刀具磨损对工件表面粗糙度的影响进行了研究。分析结果表明进给量对已加工表面的粗糙度影响最大,切削深度次之,切削速度最小;刀具进入正常磨损阶段后,表面粗糙度减小,处于最佳的切削状态。     

PVD涂层与未涂层硬质合金刀具切削力的对比试验研究

应用同型号未涂层、TiN涂层和TiCN涂层硬质合金刀具进行切削试验 ,用KISTLER三向测力仪、电荷放大器和PC机组成的切削力数据采集系统进行三向切削力采集。试验表明在切削过程中PVD涂层硬质合金刀具的切削力随刀具进给量、切削深度、切削速度的变化规律与未涂层硬质合金刀具相同 ,但涂层硬质合金刀具的切削力明显小于未涂层硬质合金刀具的切削力     

PVD涂层与未涂层硬质合金刀具切削刀的对比试验研究

应用同型号未涂层、TiN涂层和TiCN涂层硬质合金刀具进行切削试验，用KISTLER三向测力仪、电荷放大器和PC机组成的切削力数据采集系统进行三向切削力采集。试验表明在切削过程中PVD涂层硬质合金刀具的切削力随刀具进给量、切削深度、切削速度的变化规律与未涂层硬质合金刀具相同，但涂层硬质合金刀具的切削力明显小于未涂层硬质合金刀具的切削力。     

WC-Ni3Al硬质合金切削奥氏体不锈钢的切削力及磨损研究

采用正交试验法对WC-Ni3Al硬质合金刀具切削奥氏体不锈钢过程中的切削力及磨损性能进行研究,并对切削深度、进给量以及切削速度对切削力的影响进行分析。利用指数回归分析建立主切削力的经验公式,结合切削用量显著性分析对主切削力进行了对比分析。试验表明:切削深度对切削力的影响最大;与WC-Co硬质合金相比,WC-Ni3Al硬质合金刀具的切削力以及后刀面磨损均优于WC-Co刀具。     

涂层硬质合金刀具切削奥氏体不锈钢切削力的试验研究

通过四种涂层硬质合金刀具切削奥氏体不锈钢1Cr18Ni9Ti的试验,研究了切削用量对切削力的影响,并对四种刀具的切削力进行了对比分析。试验结果表明:在采用小进给量、小背吃刀量切削时,出现了背向力大于主切削力的现象;随着切削速度的增加,YBC251、GC2025刀具的切削力先减小后增大;同型号的PVD涂层硬质合金刀具与CVD涂层硬质合金刀具相比较,前者的切削力显著小于后者。     

涂层硬质合金刀具车削50钢的切削力与刀具磨损机理研究

涂层工艺可以提高硬质合金刀具的切削性能。以发动机主轴、锻造齿轮和轧辊等机械零件上广泛应用的50正火钢作为研究对象,采用多层涂层硬质合金刀具进行车削加工试验,研究切削参数对切削力的影响规律以及高速干车削条件下刀具的磨损机理。研究结果表明：切削速度v<250m/min时,三向切削力随着切削速度的增大而减小,随着切削深度的增大而增大,随着进给量的增大先减小后增大。涂层硬质合金刀具的主要磨损形态有硬质点磨损和黏结磨损,其中硬质点磨损贯穿刀具磨损全过程;刀具在不同磨损阶段有不同程度的扩散磨损和氧化磨损。涂层硬质合金刀具破损时出现崩刃、涂层剥落、裂纹破损和积屑瘤等现象。     

Inconel718合金高速切削加工的工艺参数优化

高温合金Inconel718（铬镍铁合金）的高速切削加工具有重要意义。对高速切削加工过程中Inconel718的可切削性进行试验研究,通过对切削力、切削温度、切屑形貌和材料声发射（AE）状态的观察,进行加工参数优化。试验中使用嵌入式碳化钨硬质合金（K20）刀具,在高速精密VDF车床干切削条件下进行Inconel718ff金的高速切削。结果表明,能够获得最佳加工质量的切削速度为45～55m／min。进给量为0．08mm／r,切削深度为0．5mm。     

精密切削加工Inconel718镍基高温合金的涂层硬质合金刀具磨损试验研究

Inconel718镍基高温合金适用于高温高压、高频应力应变及腐蚀环境,被广泛应用于核电、航天、航空等领域.针对核级Inconel718镍基高温合金开展精密切削加工试验,研究不同工艺参数对涂层硬质合金刀具磨损的影响.结果 表明:涂层硬质合金刀具前后刀面极易发生磨损,出现月牙洼磨损、沟槽磨损以及崩刃;车削三要素中进给量对后刀面磨损量VB的影响最为明显,随着进给量的增大,后刀面磨损量VB逐渐减小.     

PCBN刀具高速切削钛合金切削性能研究

采用PCBN刀具对钛合金TC4进行了高速车削试验,从切削力、工件表面粗糙度和刀具寿命等方面分析了PCBN刀具加工钛合金的切削性能,并与未涂层硬质合金刀具、涂层硬质合金刀具作了比较,证明了在高切削速度、低进给量和小背吃刀量的条件下,PCBN有着较长的刀具寿命。     

Some studies on hard turning of AISI 4340 steel using multilayer coated carbide tool

Hard turning with multilayer coated carbide tool has several benefits over grinding process such as, reduction of processing costs, increased productivities and improved material properties. The objective was to establish a correlation between cutting parameters such as cutting speed, feed rate and depth of cut with machining force, power, specific cutting force, tool wear and surface roughness on work piece. In the present study, performance of multilayer hard coatings (TiC/TiCN/Al₂O₃) on cemented carbide substrate using chemical vapor deposition (CVD) for machining of hardened AISI 4340 steel was evaluated. An attempt has been made to analyze the effects of process parameters on machinability aspects using Taguchi technique. Response surface plots are generated for the study of interaction effects of cutting conditions on machinability factors. The correlations were established by multiple linear regression models. The linear regression models were validated using confirmation tests. The analysis of the result revealed that, the optimal combination of low feed rate and low depth of cut with high cutting speed is beneficial for reducing machining force. Higher values of feed rates are necessary to minimize the specific cutting force. The machining power and cutting tool wear increases almost linearly with increase in cutting speed and feed rate. The combination of low feed rate and high cutting speed is necessary for minimizing the surface roughness. Abrasion was the principle wear mechanism observed at all the cutting conditions.     

Study of surface quality in high speed turning of Inconel 718 with uncoated and coated CBN tools

Inconel 718 is known to be among the most difficult-to-machine materials due to its special properties which cause the short tool life and severe surface damages. The properties, which are responsible for poor machinability, include rapid work hardening during machining; tendency to weld with the tool material at high temperature generated during machining; the tendency to form a built-up edge during machining; and the presence of hard carbides, such as titanium carbide and niobium carbide, in their microstructure. Conventional method of machining Inconel 718 with cemented carbide tool restricts the cutting speed to a maximum 30?m/min due to the lower hot hardness of carbide tool, high temperature strength and low thermal conductivity of Inconel 718. The introduction of new coated carbide tools has increased cutting speed to 100?m/min; nevertheless, the time required to machine this alloy is still considerably high. High speed machining using advanced tool material, such as CBN, is one possible alternative for improving the productivity of this material due to its higher hot hardness in comparison with carbide tool. This paper specifically deals with surface quality generated under high speed finishing turning conditions on age-hardened Inconel 718 with focus on surface roughness, metallographic analysis of surface layer and surface damages produced by machining. Both coated and uncoated CBN tools were used in the tests, and a comparison between surfaces generated by both tools was also discussed.     

Influence of machining parameters on the machinability of particulate reinforced Al/SiC–MMC

The paper presents the result of an experimental investigation on the machinability of silicon carbide particulate aluminium metal matrix composite during turning using a rhombic uncoated carbide tool. The influence of machining parameters, e.g. cutting speed, feed and depth of cut on the cutting force has been investigated. The influence of the length of machining and cutting time on the tool wear and the influence of various machining parameters, e.g. cutting speed, feed, depth of cut on the surface finish criteria has been analyzed through the various graphical representations. The combined effect of cutting speed and feed on the flank wear has also been investigated. The influence of cutting speed, feed and depth of cut on the tool wears and built-up edge is analyzed graphically. The job surface condition and wear of the cutting tool edge for the different sets of experiments have been examined and compared for searching out the suitable cutting condition for effective machining performance during turning of Al/SiC-MMC. Test results show that no built-up edge is formed during machining of Al/SiC-MMC at high speed and low depth of cut. From the test results and different SEM micrographs, suitable range of cutting speed, feed and depth of cut can be selected for proper machining of Al/SiC-MMC.     

Experimental estimation and optimization of process parameters under minimum quantity lubrication and dry turning of AISI-4340 with different carbide inserts

An experimental study has been performed on AISI 4340 steel in this paper. The influence of approach angle, feed rate, cutting speed and depth of cut has been on cutting forces and tool tip temperature has been experimentally investigated. Before conducting experiments on the AISI 4340 steel work-piece, the chemical composition test, microstructure test were performed and hardness of the work-piece was improved by heat treatment. A total of 64 experiments each by two different coated carbide inserts (PVD and CVD-coated) were conducted on AISI-4340 steel under different environmental conditions (dry and MQL machining). During the experiments, approach angle, cutting speed, feed rate are varied to four levels and the depth of cut is kept constant to investigate the effect of the same on the three cutting forces component and the temperature variations on the tool-tip. It is observed that the main cutting force was largest among the three cutting force components in case of AISI 4340 steel turning and MQL machining show beneficial effects compared to dry machining.     

Improving surface integrity in finish machining of Inconel 718 alloy using intelligent systems

In machining of hard materials, surface integrity is one of the major customer requirements which comprise the study of the changes induced to the workpiece. Surface roughness and residual stress are often considered as the most significant indications of surface integrity. Inducing tensile residual stress during the machining processes is a critical problem which should be avoided or minimized to obtain better service quality and component life. This problem becomes more evident in the presence of rough machined surface because fatigue life of manufactured components might be decreased significantly. Inconel 718 superalloy is one of the hard materials used extensively in the aerospace industries. It is prone to tensile residual stress in machined surface. Thus, controlling and optimizing residual stress and surface roughness in machining of Inconel 718 are so needed. Intelligent techniques based on the predictive and optimization models can be used efficiently for this purpose. In this study, the optimal machining parameters including cutting speed, depth of cut, and feed rate were accessed by intelligent systems to evaluate the state of residual stress and surface roughness in finish turning of Inconel 718. The results of experiments and analyses indicated that implemented techniques in this work provided a robust framework for improving surface integrity in machining of Inconel 718 alloy. It was shown that cutting speed has more effect on surface integrity than other investigated parameters. Also, depth of cut and feed rate were found in the moderate range to obtain satisfactory state of tensile residual stress and surface roughness.     

Effect of cutting parameters on the degree of work hardening and tool life during high-speed machining of Inconel 718

The use of superalloy Inconel 718 is increasing in most of the sophisticated applications like aircraft engines, industrial gas turbines, rocket engines, space vehicles, submarines, etc. Hence, in-depth understanding of this material helps to determine the ability of this material to withstand severe conditions of stress, temperature, corrosion, and controls its longevity and reliability. In the present work, an attempt has been made to study the relationship of degree of work hardening and tool life as a function of cutting parameters like cutting speed, feed, depth of cut, untreated tungsten carbide and postcryogenic-treated tool. Work hardening and tool life are the major factors which need to be controlled/improved to enhance the machinability characteristics of superalloy Inconel 718. A significant performance in tool life was observed due to cryogenic treatment given to tungsten carbide tool. Moreover, it was observed that optimized cutting parameters not only minimized/controlled work hardening characteristics but also improved tool life while high-speed machining of Inconel 718.     

Wear mechanisms of WC coated and uncoated tools in finish turning of Inconel 718

This paper presents the results of an experimental investigation on the wear mechanisms of uncoated tungsten carbide (WC) and coated tools (single-layer (TiAlN) PVD, and triple-layer (TiCN/Al₂O₃/TiN) CVD) in oblique finish turning of Inconel 718. Tool wear rate and wear mechanisms were evaluated for cutting speeds, 50<V<100 m/min, and feed rates, 0.075<f<0.125 mm/rev, at a constant depth of cut of 0.25 mm. It was concluded that abrasive and adhesive wear were the most dominant wear mechanisms, controlling the deterioration and final failure of the WC tools. While the triple layer CVD coated tools exhibited the highest wear resistance at high cutting speeds and low feeds, uncoated tools outperformed the single and multi-layer coated tools in the low range of cutting speeds and intermediate feeds. The cutting tool with single-layer PVD coating outperformed the other tools at the medium cutting speed.     

Finish Machining of Nickel-Base Inconel 718 Alloy with Coated Carbide Tool under Conventional and High-Pressure Coolant Supplies

Single-point turning of Inconel 718 alloy with commercially available Physical Vapour Deposition (PVD)-coated carbide tools under conventional and high-pressure coolant supplies up to 20.3 MPa was carried out. Tool life, surface roughness (Ra), tool wear, and component forces were recorded and analyzed. The test results show that acceptable surface finish and improved tool life can be achieved when machining Inconel 718 with high coolant pressures. The highest improvement in tool life (349%) was achieved when machining with 11 MPa coolant supply pressure at higher speed conditions of 60 m · min^?1. Machining with coolant pressures in excess of 11 MPa at cutting speeds up to 40 m · min^?1 lowered tool life more than when machining under conventional coolant flow at a feed rate of 0.1 mm · rev^?1. This suggests that there is a critical coolant pressure under which the cutting tools performed better under high-pressure coolant supplies.

Cutting forces increased with increasing cutting speed due probably to reactive forces introduced by the high-pressure coolant jet. Tool wear/wear rate increased gradually with prolonged machining with high coolant pressures due to improved coolant access to the cutting interface, hence lowering cutting temperature. Nose wear was the dominant tool failure mode when machining with coated carbide tools due probably to a reduction in the chip-tool and tool-workpiece contact length/area.