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The milling stability of thin-walled components is an important issue in the aviation manufacturing industry, which greatly limits the removal rate of a workpiece. However, for a thin-walled workpiece, the dynamic characteristics vary at different positions. In addition, the removed part also has influence on determining the modal parameters of the workpiece. Thus, the milling stability is also time-variant. In this work, in order to investigate the time variation of a workpiece’s dynamic characteristics, a new computational model is firstly derived by dividing the workpiece into a removed part and a remaining part with the Ritz method. Then, an updated frequency response function is obtained by Lagrange’s equation and the corresponding modal parameters are extracted. Finally, multi-mode stability lobes are plotted by the different quadrature method and its accuracy is verified by experiments. The proposed method improves the computational efficiency to predict the time-varying characteristics of a thin-walled workpiece.

To provide guidance for the tool materials selection in the machining of high-strength steels, this article outlines the application of fuzzy comprehensive evaluation method for the cutting performance evaluation of cemented carbide tools, ceramic tools, and cermet tools. The results indicate that cermets with the best comprehensive cutting performance are chosen as the optimum tool materials for the machining of high-strength steels. Moreover, the severe adhesion wear characteristics of cemented carbide tools are detrimental to the surface quality of workpieces. The obvious crater wear and furrow-like scratches caused mainly by abrasive wear, as well as adhesive wear can shorten the life of ceramic tools. The sharp cutting edge and good wear resistance of cermet tools are not only beneficial to the machined surface quality of workpieces, but also prolong the tool life. The analysis of tool wear proves the reliability and accuracy of fuzzy comprehensive evaluation method.

Deuterated polymer microspheres can be used as a neutron source in conjunction with lasers because thermonuclear fusion neutrons can be produced efficiently by collisions of the resulting energetic deuterium ions. A new type of solid deuterated polymer microsphere with a carbon hydrogen–carbon deuterium (CH-CD) multilayer has been designed for preparing the target for inertial confinement fusion (ICF) experiments. To fabricate these solid CH-CD multilayer microspheres, CH beads are first fabricated by a microfluidic technique, and the CD coating layer is prepared by a plasma polymerization method. Both polystyrene (PS) and poly(α-methylstyrene) (PAMS) are used as the material sources for the CH beads. The effects of the PS and PAMS materials on the quality of the solid CH beads and the resulting CH-CD multilayer polymer microspheres are investigated. The solid PS beads have better sphericity and a smoother surface, but large vacuoles are observed in solid PS-CD multilayer microspheres owing to the presence of residual fluorobenzene in the beads and a glass transition temperature of the solid PS beads that is lower than the temperature of plasma polymerization. Therefore, solid PAMS beads are more suitable as a mandrel for fabricating solid CH-CD multilayer polymer microspheres. Solid CH-CD multilayer microspheres with specified size have been successfully prepared by controlling the droplet size and the CD deposition rate and deposition time. Compared with the design value, the diameter deviation of the inner CH beads and the thickness deviation of the CD layer can be controlled within 20 µm and 2 µm, respectively. Thus, an approach has been developed to fabricate solid CH-CD multilayer microspheres that meet the physical design requirements for ICF.

The study in this paper focuses on surface morphology and crack formation of 7050-T7451 aluminum alloy in high-speed milling, from 3000 to 5000 m/min. The surface roughness of machined workpiece was investigated with optical profiler; minimum R a and R q value were obtained at the cutting speed of 5000 m/min. Defects such as smeared material, metal debris, and feed marks on workpiece surface were observed with scanning electron microscope. One kind of edge-oxidized feed mark was found on surface. Width of it was measured and two hypotheses were introduced to interpret this phenomenon. Based on the hypothesis, the workpiece surface was determined to be formed at cut-off process. Two kinds of microcracks were observed on Al7Cu2Fe and Mg2Si phase. Those cracks showed different orientations, and this was helpful for interpreting the formation of microcracks in high-speed machining. The heat imposed to surface was connected with cracks on different phases. The results provided a complete view of surface morphology generation and microcrack-formation mechanism in high-speed cutting process. The two aspects of this research were helpful for controlling the integrity of surface and prolong service life of workpiece.

Based on the concept of cleaner production, the feasibility of application of the flue gas in mine mouth power to fire prevention and extinguishing in goaf was numerically studied by taking the mechanized caving mining face 11-214 of Caocun coal mine as the example. The heterogeneity porosity and multi-component gas transport equations were introduced into the mathematical model. The calculated results showed that the area of “spontaneous combustion zone” turn small obviously in goaf and the maximum width of “spontaneous combustion zone” in goaf decreased from 78m to 9.5m after injecting the flue gas. At the same time, the sink terms of oxygen consumption was formed in the port of gas injection. The migration law of flue gas showed that the numerical calculation of goaf should select the different computation model based on the judgment basis of Reynolds number. Through the continuous monitoring of the migration of flue gas at different locations in goaf, the reasonable parameters of flue gas injection was obtained for high efficient fire prevention .

Considering the self-excited and forced vibrations in peripheral milling processes, a novel optimization method of cutting parameters is presented. The optimization method proposed, which is based on the vibration frequency analysis during milling processes, can achieve the most stable cutting process in relative stable region (or conditional stable region). First, relationships between vibration frequencies and phase angle of tooth of cutter in milling processes are investigated. Four kinds of spindle speeds associated with several bifurcations and vibrations are defined. Second, chatter-free regions are subdivided according to these spindle speeds. It is shown that in the so-called subregion C, cutting parameters can be simultaneously optimized for higher material removal rate (MRR) and higher surface accuracy. Third, optimal control theory is employed to determine the optimal cutting parameters, which can achieve the most stable cutting process in relative stable region. Optimizations of spindle speeds and depth of cut are conducted by using the stability charts and performance contours diagrams. The results show that the optimal cutting parameters can also be obtained in the so-called subregion C. Finally, the numerical results are verified and analyzed through milling experiments.

Aerodynamic noise spectrum of rotary face milling cutters consists of a broad range of high frequencies and discrete tones. This paper aims to develop a method to calculate the aerodynamic noise generation and propagation by rotary face milling cutters. The effects of milling cutter geometry on the generation of aerodynamic noise are analyzed. Based on the computational fluid dynamics (CFD) method, the Ffowcs Williams–Hawkings (FW–H) equation is used to predict the sound pressure level (SPL) of aerodynamic noise in face milling cutters. The accurate calculation of time-varying flow variables along with the rotation of cutter is very important for the prediction of aerodynamic noise. In this case, the Navier–Stokes (N–S) equation is employed to evaluate the pressure and velocity fields around the milling cutters, first in a steady mode with the Multiple Reference Frames (MRF) model, and then in an unsteady mode with sliding mesh technique (SMT) by introducing the steady flow variables as its initial fields. It is found that both the overall aerodynamic noise due to the entire cutter and the aerodynamic noise only due to the cutter gullet regions are significantly affected by the number of cutter teeth/gullet regions. Moreover, six representative milling cutters with different tooth numbers and geometries of gullet regions are chosen to study the effects of gullet configuration on aerodynamic noise generation, and the characteristics of noise spectra generated by the cutters are analyzed. The aerodynamic noise generated only by the cutter gullet regions is found to be strongly dependent on the gullet design-volume and shape. The results also reveal that the gullet design advantage of Cutter C in reducing noise generation among the eight-tooth designs, and the gullet design advantage of Cutter A in reducing noise generation among the five and seven-tooth designs in this investigation.

A generalized cutting mechanics model is proposed for milling processes with solid end mills and inserted cutters. The unified mathematical model is employed for the description of the solid milling flute and insert on a reference tool body. The friction and normal forces acting on the rake face are transformed into milling coordinates using a general transformation matrix by simply assigning operation specific parameters. The generalized model can be used to predict and optimize the machining operations including solid end mills and inserted cutters.

Determination of the surface integrity is of particular importance because of its influence on workpiece service life. The microstructure of 7050-T7451 aluminum alloy under the cutting speed of 3000~5000m/min was observed in this paper. With the increase of cutting speed, microhardness was analyzed to investigate the thermal softening phenomenon engendered, which would affect the surface performance in return. According to the results, influences of cutting speed on microstruceture and microhardness in high speed were explored and further research on temperature in high speed is suggested.

This paper presents the experimental results of cutting force and surface roughness of 7050-T7451 aluminum alloy under the cutting speed of 3000~5000m/min. The cutting forces and surface roughness with different cutting parameters were analyzed. Experimental results suggested that increasing cutting speed would engender thermal softening, which would in return affect the cutting force and surface roughness in high speed milling. The cutting force and surface roughness were affected by cutting depth and feed rate obviously. Surface roughness was also affected by cutting width which changed the cutting force slightly. According to the results, proper parameters could be selected and thermodynamic relationship needed to be discussed for further research.

This paper presents investigations on turning TC4 alloy with PVD TiAlN coated cemented carbide inserts. The turning test was conducted with variable cutting speeds ranging from 80 to 120 m/min. Wear surfaces of the cutting tools are analyzed to study the wear mechanism of PVD TiAlN coated cemented carbide tools in turning of titanium alloy TC4. Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer( EDS) analyses by wear maps indicated that the wear of coated cemented carbide tools was caused by adhesion, coating delamination and mechanical fatigue. The analysis of EDS indicated no oxidation wear generated during the machining. The excellent chemical stability and oxidation resistance performance of TiAlN coating made contribution to prevent oxidation wear.

In this study, orthogonal turning experiments are performed to analyze the machinability of Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti-17), a β-rich, α+β type alloy. PVD TiAlN coated carbide tool inserts are applied, because they are used widely for machining this material. The cutting forces and cutting temperatures are examined under different cutting conditions, which the cutting speeds are varied from 44m/min to 123m/min, the feed rates are 0.06mm/r, 0.08mm/r, 0.10mm/r and 0.12mm/r,respectively.There are some different varying trends of both the cutting force and the thrust force with the change of cutting speed. The cutting temperatures are found to increase with cutting speeds as well as feed rates.

This paper deals with an experimental research on the wear mechanism of coated carbide tools in dry boring of the titanium alloys TC11 which are commonly used for aero-engines. The wear mechanism of coated tool inserts was investigated at various combinations of cutting speed, feed rate, and depth of cut. Analysis carried out with the SEM suggests that adhesive wear and coating delamination are the dominant wear mechanisms under low speed and feed rate and depth of cut; while chipping and breakage are the dominant wear mechanisms for the combinations of high cutting speed, feed rate, and depth of cut. There was no observation of oxygen existing based on the analysis of SEM which indicated no oxidation wear generated during the boring machining. The excellent chemical stability of TiAlN coating and oxidation resistance performance made contribution to prevent oxidation wear. Another reason was that boring temperature was lower than oxidation temperature.

Ti6Al4V is a difficult to machine alloy with low cutting efficiency and server tool wear. A series of orthogonal turning tests with coated carbide in higher speed scale was carried out on a CA6140 lathe. The experiential functions of tool life based on orthogonal experiment were developed. The tool wear morphologies were examined by scanning electron microscope (SEM) and energy disperse spectroscopy (EDS), adhesion, diffusion and micro-chipping were the major wear mechanisms of coated carbide tool. Finally, the cutting parameters of coated carbide tool in Ti6Al4V dry turning were optimized based on tool life-efficiency contour analysis, in same cutting efficiency, the lower cutting speed and larger depth of cut are the better selection in Ti6Al4V turning for coated carbide tool.

The efficiency of the high-speed milling process is often limited by the occurrence of chatter. In order to predict the occurrence of chatter, accurate models are necessary. With the speed increasing, gyroscopic effect plays an important pole on the system behavior, including dynamic characteristic and rotating behavior. Considering the influence of gyroscopic effect on rotating behavior, an updated model for the milling process is presented which features as model of the equivalent profile of tool. In combination with this model, a nonlinear instantaneous cutting force model is proposed. The use of this updated equivalent profile of tool results in significant differences in the static uncut thickness compared to the traditional model.

A difficult-to-machining material, cast supper alloy K24 has been cut with two different methods, milling and abrasive waterjet (AWJ). It is shown that milling is characterized by high tool cost, low efficiency, and good surface roughness while abrasive waterjet brings high efficiency and worse surface quality. The results have proven that the combination use of AWJ and milling is an efficient way in cutting K24.

The strong demand for increasing productivity and workpiece quality in milling process makes the machine-tool system operate close to the limit of its dynamic stability. Milling cutters with variable pitch angles can be very effective in improving stability against chatter for certain speed ranges, which will be predicted by the model presented here. The present paper deals with the design of structural geometry of variable pitch end mills in detail. Based on the analysis of tooth engagement factor, which is expressed and extended in the paper, an approach is proposed to design variable pitch end mill with high milling stability. The certain speed ranges with high milling stability are given.

Vibration frequencies during high-speed milling processes are investigated. Based on the resonant theory and three critical stats of phase position of successive two cutter teeth, six kinds of spindle speeds are shown, which divide the stable region in stability limit diagram into four parts. Furthermore, using optimal control theory, a novel stable region is proposed, which divides the region into three parts (unconditional stable, optimal stable, and conditional stable region).

This paper studies the application of CBR (case-based reasoning) in stone equipments variant design. As the actual design process and CBR process have collateral corresponding relation, CBR accords with the actual design process of deviser. The basic resolution model of variant design is established, and the instance of products variant design is presented. With the application of variant design principle, the design intensity will be lightened, and the design time will be shortened. Therefore the variant design accommodates the requirement of products diversification and client orientation.

The strong demand for increasing productivity and workpiece quality in milling process makes the machine–tool system operate close to the limit of its dynamic stability. Besides predicting accurately chatter stability, it is required that some optimizations should be conducted, e.g., cutter structure, for improving the dynamic stability limits. Milling cutters with variable pitch angles can be very effective in improving stability against chatter for certain speed ranges, which will be predicted by the model presented here. The present paper deals with the design of structural geometry of variable pitch end mills in detail. Based on the analysis of tooth engagement factor, which is expressed and extended in the paper, an approach is proposed to design variable pitch end mill with high milling stability. The certain speed ranges with high milling stability are given. An example of the design of variable pitch end mills is illustrated to demonstrate the validity of this method.

ZrTiN hard coatings were deposited by multi-arc ion plating on tungsten carbide substrates, using separated Ti and Zr targets in nitrogen and argon atmosphere, combined with ion bombardment of samples surface. The films exhibited a dense and fine grained structure with no columnar growth structure. ZrTiN coatings deposited reveal a (111) preferred crystal orientation. For the coatings, solid solutions were formed. The coatings possessed a higher microhardness value (approx. 2700 Hv0.05) than their binary counterparts. The increased microhardness was probably due to a solid solution strengthening mechanism while depositing. The thickness of the coatings were between 2.0 and 2.3 μm. The adhesive strength of the coating-substrate system was up to more than 70N.

CrN and CrAlN coating tools were heated and heat-preserved in electric stove to make oxidation experiment. The results were obtained through SEM, EDX and XRD. The results are as follows: The oxidation of CrN and CrAlN coating is induced by the micro-holes which were formed by the diffusion of nitrogen atoms and chromium ions towards the coating surface under sufficient thermal energy. With the incorporation of Al, CrAlN coating showed stronger oxidation resistance as compared to CrN. The dense mixture of Cr2O3and Al2O3makes oxygen diffusion through the film difficult and then oxidation and decomposing are alleviated effectively, therefore CrAlN coating can remain high oxidation resistance and high hardness after high temperature which make this coating tool be competent for high speed machining of the hardworking materials. In addition, the failure of the coating is primary induced by oxidation and the different expansion coefficients between coating and substrate.

A method for predicting simultaneous dynamic stability limit of thin-walled workpiece high-speed milling process is described. The proposed approach takes into account the variations of dynamic characteristics of workpiece with the tool position. A dedicated thin-walled workpiece representative of a typical industrial application is designed and modeled by finite element method. The curvilinear equation of modal characteristics changing with tool position is regressed. A specific dynamic stability lobe diagram is then elaborated by scanning the dynamic properties of workpiece along the machined direction throughout the machining process. The results show that, during thin-walled workpiece milling process, material removing plays an important part on the change of dynamic characteristics of system, and the stability limit curves are dynamic curves with time–variable. In practical machining, some suggestion is interpreted in order to avoid the vibrations and increase the chatter free material removal rate and surface finish. Then investigations are compared and verified by high-speed milling experiments with thin-walled workpiece.

The thermal stresses generated in ZrTiN coating deposited on HSS and tungsten carbide substrates are investigated by finite element analysis and calculated by mathematics model. FEM analysis provides detailed information about all stress components. The influence of deposition temperature, substrate materials, coating thickness and interlayers on the generation is analyzed. The thermal stress of coatings has a linear relationship with deposition temperature, and an inverse relationship with the coating thickness. The results of simulated thermal stress are in accordance with the analytical method. The highest shear stress found at the interface between the coating and substrate indicates that the interface is the critical location which is learned from the failure point of view. Results also show that the insertion of TiZr interlayer between the coating and substrate can reduce the stress components especially the shear stress. The interlayer thickness has a great effect on stress reduction.

Ti6Al4V is a difficult to machine alloy with low cutting efficiency and server tool wear. A series of orthogonal milling tests with coated and uncoated carbide insert was carried out. The tool life predictive models based on orthogonal experiment were developed. Finally, the cutting parameters for both tools in Ti6Al4V dry milling were optimized based on tool life-efficiency contour analysis.

In the present paper, a dynamic modeling approach is presented to determine the contact stiffness and structural damping between the spindle and the toolholder; and then, the spindle and the toolholder are coupled by some springs and dampers. Finally, the dynamic performances of the HSK-A63 spindle/toolholder interface are analyzed by means of finite element method (FEM). From the simulated results, it can be seen that the natural frequencies of the first two modes increase with the increase of the rotational speed, which make the HSK spindle/toolholder interface appear good dynamic performances and be suitable for high-speed machining.

During the high-speed milling operations of 7050-T7451 aluminum alloy using solid carbide end mills, helical angle, axial and radial depth-of-cut have significant effects on the milling uniformity. A surface roughness predictive model of work-piece was developed by using a full-factorial experimental design and multi-linear regression technology. Genetic algorithm was utilized to optimize the helical angle and cutting parameters by means of a series of operations of selection, crossover and mutation based on genetics. The result shows that it is possible to select optimum axial depth-of-cut, radial depth-of-cut and helical angle for obtaining minimum cutting force and reasonably good metal removal rate.

The granite cutting processing using diamond circular saw blades is the most extensive application processing methods. The cutting force is measured at different cutting depth ap, sawing feed rate vf and linear velocity v when the granite is cut by diamond circular saw blade by orthogonal experimental method. And the sawing force empirical formulas relative to these three variables are educed. We can obtain the experimental results as follows. The radial force Fn is greater than the tangent force Ft when ap is smaller than the circular saw blade diameter. The corresponding Fn and Ft are all smaller as the feed rate is greater at the same circular saw blade diameter. The cutting forces increase obviously as the cutting depth increases at the same circular saw blade diameter and feed rate.

A new approach is presented to optimize the tool life of solid carbide end mill in high-speed milling of 7050-T7451 aeronautical aluminum alloy. In view of this, the multi-linear regression model for tool life has been developed in terms of cutting speed and feed per tooth by means of central composite design of experiment and least-square techniques. Variance analyses were applied to check the adequacy of the predictive model and the significances of the independent parameters. Response contours of tool life and metal removal rates were generated by using response surface methodology (RSM). The analysis results show that it is possible to select an optimum combination of cutting speed and feed per tooth that improves metal removal rate without any sacrifice in tool life.

A method for predicting the stability of thin-walled workpiece milling process is described. The proposed approach takes into account the dynamic characteristics of workpiece changing with tool positions. A dedicated thin-walled workpiece representative of a typical industrial application is designed and modeled by finite element method (FEM). The workpiece frequency response function (FRF) depending on tool positions is obtained. A specific 3D stability chart (SC) for different spindle speeds and different tool positions is then elaborated by scanning the dynamic properties of workpiece along the machined direction throughout the machining process. The dynamic optimization of cutting parameters for increasing the chatter free material removal rate and surface finish is presented through considering the chatter vibration and forced vibration. The investigations are compared and verified by high speed milling experiments with flexible workpiece.

The machining processes could induce residual stresses that enhance or impair greatly the performance of the machined component. Machining residual stresses correlate very closely with the cutting parameters and the tool geometries. In this paper, the effect of the tool flank wear on residual stresses profiles in milling of aluminum alloy 7050-T7451 was investigated. In the experiments, the residual stresses on the surface of the workpiece and in-depth were measured by using X-ray diffraction technique in combination with electro-polishing technique. In order to correlate the residual stresses with the thermal and mechanical phenomena developed during milling, the orthogonal components of the cutting forces were measured using a Kistler 9257A type three-component piezoelectric dynamometer. The temperature field of the machined workpiece surface was obtained with the combination of infrared thermal imaging system and finite element method. The results show that the tool flank wear has a significant effect on residual stresses profiles, especially superficial residual stress. As the tool flank wear length increases, the residual stress on the machined surface shifts obviously to tensile range, the residual compressive stress beneath the machined surface increases and the thickness of the residual stresses layer also increases. The magnitude and distributions of the residual stresses are closely correlated with cutting forces and temperature field. The three orthogonal components of the peak cutting forces increase and the highest temperature of the machined workpiece surface also increases significantly with an increase in the flank wear. The results reveal that the thermal load plays a significant role in the formation of the superficial residual stress, while the dominative factor that affects thickness of residual stresses layer is the mechanical load in high-speed milling aluminum alloy using worn tool.

The strong demand for increasing productivity and workpiece quality in high-speed milling make the machine-tool system has to operate close to the limit of its dynamic stability. This requires that the chatter stability is predicted accurately to determine the optimal milling parameters. An analytical stability prediction method was proposed with multi-degree-of-freedom (MDOF) system modal analysis. This paper describes the development of this new method which allows considering the effects of multi-mode dynamics of system, higher excited frequency (i.e. tooth passing frequency) and wider spindle speed range on stability limits in high-speed milling, and these to help in selection of milling parameters for a maximum material removal rates (MRR) in real operations without chatter. Some tests were carried out to demonstrate the quality of this method used in real machining. Final, the main influencing factors of stability limits in high-speed milling were analyzed.

In this paper, the formulae of transient temperature field and transient thermal stress field in an infinite sandwich plate with double-sided functionally graded coatings (FGM coatings) under the convective boundary condition are derived via an asymptotic solution approach. The thermo-physical properties of the two symmetrical graded coatings are assumed to have distributions of power forms along the thickness direction of the plate. Numerical calculations of transient thermal stresses for a TiC–Al2O3 FGM coating/Al2O3 substrate/Al2O3–TiC FGM coating system under different Biot numbers in cold shock are performed in contrast to a sandwich plate with homogeneous coatings and a homogeneous plate. The effects of the thermo-physical property distributions of the FGM coatings on the thermal shock resistance of the plate are analyzed. And consequently some design rules for the sandwich plate with FGM coatings are put forward, which may be used to design FGM coated cutting tools with high thermal shock resistance.

In this paper, the components of a high-speed cutting system are analyzed firstly. The component variables of the high-speed cutting system are classified into four types: uncontrolled variables, process variables, control variables, and output variables. The relationships and interactions of these variables are discussed. Then, by analyzing and comparing intelligent reasoning methods frequently used, the hybrid reasoning is employed to build the high-speed cutting database system. Then, the data structures of high-speed cutting case base and databases are determined. Finally, the component parts and working process of the high-speed cutting database system on the basis of hybrid reasoning are presented.

The present work puts forward a generalized simulation model to evaluate the topography of ball-end milled surfaces by considering both the tool deflection and the tool runout. Firstly, a solid ball-end mill with S-shaped cutting edges is modeled as the basis. Then the tool tip trajectory is derived from the tool runout as well as the cutting forces induced tool deflection. And consequently the topography and scallop height of the machined surface are estimated by the numerical calculations of the matrix equations. With good expandibility, the proposed model can incorporate more machining information such as the movements of rotatory axes and tool wear, and hence, can be used to optimize the cutting conditions and parameters in 5-axis ball-end milling process.

A new dynamics model for multi-degree of freedom high-speed milling system is proposed, which takes account of regenerative effects and the effects of the relative vibration of spindle axis in milling process. Based on the mode synthesis theory and the zeroth-order approximation of the Fourier series, an integrated stability analytical method for multiple frequencies is presented, which involves multiple orders modal characteristics and higher order excitations in high-speed milling process. The chatter stability lobes are predicted in the frequency domain using the proposed stability analytical method, and verified by milling experiments. It is shown that stability regions involving multiple natural modes are reduced contrary to the case of single natural mode.

In this paper, the transient heat conduction and transient thermal stresses in an infinite plate with double-sided functionally graded coatings (FGM coatings) under the convective boundary condition are investigated. The thermo-physical properties of the two symmetrical FGM coatings are assumed to have distributions of power forms along the thickness direction of the plate, the effects of which on the thermal shock resistance of the FGM coated plate are analyzed via numerical calculations. And consequently some design rules for the double-sided FGM coatings are put forward, which provide a guidance for the development of FGM coated cutting tools.

In this paper, multi-linear regression and artificial neural network (ANN) models have been developed to predict surface roughness in high-speed milling of 7050-T7451 aluminum alloy. Surface roughness is taken as the response variable, while cutting speed, feed per tooth, radial depth of cut and slenderness ratio are taken as independent input parameters. An orthogonal experiment design is developed to conduct experiments. The measured values of surface roughness are used to find the regression coefficients and train the neural network for prediction of surface roughness. Predicted values of surface roughness by both models are compared with the measured values.

The HSK spindle/toolholder interface belongs to the complicated nonlinear contact problem caused by taper interference fit. The experiment and the traditional Lame's equation are all not suited for analyzing the contact stress distribution and deformation in the spindle/toolholder interface. In this paper, the contact stress distribution and the deformation of the HSK-A63 spindle/toolholder interface caused by the taper interference fit were precisely simulated by means of the finite element method. The simulated results showed that the toolholder shank was in partial contact with the spindle bore, the interference specified by ISO was not enough for the high-speed machining and larger interference should be introduced.

Accurately material constitutive model is essential to understand and predict machining process. High temperature split Hopkinson pressure bar (SHPB) test system is used to investigate flow stress behavior and characteristics of 7050-T7451 aluminum alloy. Specimens are tested from 200°C to 550°C at intervals of 50°C and room temperature, at strain-rate of 2800s-1. The experimental results show that flow stress is strongly dependent on temperature as well as strain rate, flow stress decreases with the increase of temperature, while increase with the increasing of strain rate. The material parameters are determined for both Johnson-Cook constitutive equation and modified Johnson-Cook constitutive equation. The modified JC equation is more suitable for expressing the dynamic behavior of 7050-T7451 aluminum alloy.

With the advantage of Case-Based Reasoning (CBR), selection method about matching of cutting tools with workpiece materials is presented through establishing the matching knowledge and rules in such respects as mechanical, physical and chemical properties of cutting and workpiece materials. Intelligent matching system of cutting tools with workpiece materials is developed based on CBR. This system has such advantages as higher matching speed and better accuracy, which offers a strong support tool for material selection between the cutter and workpiece.

This paper focuses on developing an empirical model for the prediction of milling forces in high-speed end milling of P20 die-mold steel. The spindle speed, feed rate, axial and radial depth of cut are considered as the affecting factors. The data for establishing the model are derived from high-speed end milling experiments conducted on a 5 axis machining center according to the principles of DOE (design of experiments) method. The influences of milling parameters on milling forces are investigated by analyzing the experimental curves. Consequently, multiple-regression analysis is applied in developing the empirical model. Furthermore, the significances of the regression equation and regression coefficients are statistically tested in this paper to validate the model.

High-speed machining (HSM) has received great interest because it leads to an increase of productivity and a better workpiece surface quality. However, tool wear increases dramatically due to the high temperature at the tool/workpiece interface. Proper selection of cutting tool and cutting parameters is the key process in high-speed machining. In this paper, experiments have been conducted to high speed milling pearlitic cast iron with different tool materials, including polycrystalline cubic boron nitrogen, ceramics and coated cemented carbides. Wear curves and tool life curves have been achieved at various cutting speeds with different cutting tools. If efficiency is considered, Polycrystalline Cubic Boron Nitrogen cutting tool materials are preferred in finish and semi-finish machining. According to the different hardness of cast iron, the appropriate range of cutting speed is from 850 m/min to 1200m/min.

During high-speed machining, in order to make cutting tools work reliably and obtain ideal machining quality, not only good static characteristics, but also good dynamic characteristics are necessary. In this paper, with the help of the close combination of experimental research and modal parameter identification technique, the dynamic characteristics of the machine tool/cutting tool system were analyzed. Experimental results indicated that studying the effect of the dynamic characteristics on cutting force, machining accuracy and surface roughness could provide theoretical basis for effectively excluding the resonance zone that obviously destroyed machining quality and then optimizing cutting parameters further.

In this paper we present a multifunctional combined CNC machine that integrates the technology of USM, EDM and grinding. For non-conductive hard and brittle materials, the machine tool could perform ultrasonic machining and grinding machining combined ultrasonic vibration; for conductive hard and brittle materials, electrical discharge with or without ultrasonic vibration could be implemented. Conductive engineering ceramics have been used for elementary experiments, the results show that it is more efficient and more stable for processing this kind of materials by using the multifunctional combined CNC machine. On the basis of brief introduction about the structure of the machine tool, this paper emphasizes the form of control system, the gap state inspection that can be used to ensure the stability in processing and the principle for servo control.

Cutting tool and machining parameters selection are central activity in process planning, which was traditionally performed by numerical control programmers or machine tool operators. The surface integrity has great effect on part quality and the sudden tool failure increases the machining costs greatly. The present paper details the development of a cutting database system with surface integrity prediction and tool failure analysis functions (CUT-P&A). The design and implement of this system has been presented. The system includes three main modules: cutting database, premature tool failure analysis and surface integrity prediction. The functions of this system include cutting tool selection and machining parameters recommendation, prediction of surface integrity and premature tool wear analysis. A case has been studied to explain the application of the system. The wide application of this system will be helpful for machining tool programmers, the improvement of machined part quality and the reduction of machine cost.

High-speed machining has become mainstream in machining manufacturing industry. In industries such as moldmaking and aerospace, it has become the norm rather the exception. The centrifugal force increases as the square of the speed. At rotational spindle speeds of 6,000 r/min and higher however, centrifugal force from unbalance becomes a damaging factor and it reduces the life of the spindle and the tool, as well as diminishes the quality of the finished product. Under high rotational speed, good balance becomes issue. High-speed machining experimental results shown that a well-balanced tool/toolholder assembly could obviously improve machining quality, extend tool life and shorten downtime for spindle system maintenance etc.

As the actual design process and CBD process have collateral corresponding relation, CBD accords with the actual design process of deviser. This paper studies the application of CBD technology in product variant design. The basic resolution model of variant design is established, and the instance of products variant design is presented. With the application of variant design principle, the design intensity will be lightened, and the design time will be shortened. Therefore the variant design could accommodate the requirement of product diversification and client orientation.

Thermal shock resistance is one of the primary properties for the ceramic cutting tool materials with perspectives in high speed machining. An optimum model for the compositional design of the composite ceramic tool materials is built based on the thermal shock resistance. The thermal stress fracture resistance factor R is used to characterize the thermal shock resistance of the ceramic material. Results show that the developed (W,Ti)C/SiC/Al2O3 multiphase ceramic tool material can be expected to achieve the highest thermal shock resistance when the volume fraction of (W,Ti)C and SiC is about 15.8% and 24.8%, respectively. Thermal fracture resistance of the (W,Ti)C/SiC/Al2O3 ceramic tool material is approximately 81-88% higher than that of the pure alumina ceramic when machining the hardened carbon steel, which coincides well with the theoretical prediction from the optimum model. It suggests that the method used here is feasible for the development of ceramic tool materials with designed thermal shock resistance.