Showing papers on "Honing published in 2017"

A novel magnetorheological honing process for nano-finishing of variable cylindrical internal surfaces

Abstract: A novel magnetorheological honing process is designed and developed for nano-finishing of cylindrical internal surfaces with the help of permanent magnets. The radial movement of magnetic tool surface is adjusted as per the internal diameter of different cylindrical components and make it fixed before start of finishing so that it can maintain constant working gap while perform finishing. The present developed magnetic tool surface always constitutes higher magnetic field than the inner surface of ferromagnetic or non-ferromagnetic cylindrical workpiece. This is an important requirement to finish the internal surface of ferromagnetic or non-ferromagnetic cylindrical components because it ensures MR polishing fluid cannot stick on the workpiece surface while performing the finishing. Hence, present developed process is useful for finishing of ferromagnetic cylindrical molds, dies, hydraulic actuators, etc. for its better functional applications after the conventional honing or grinding process. The...

An efficient honing method for face gear with tooth profile modification

Abstract: To improve the production efficiency of the face gear, this paper studies a honing method for face gear with tooth profile modification and proposes a face gear honing principle. Based on the honing principle, a mathematical model of the face gear honing cutter is derived. The tooth profile of the honing cutter is modified by controlling the longitudinal modification coefficient of the generating rack cutter. Then, the tooth flank equation of the honed face gear is derived according to the machine structure. To ensure the face gear accuracy, an error analysis model including the axial, tangential, and radial tool setting errors is presented, and the effects of tool setting errors on the face gear geometry errors are analyzed. The honing cutter is manufactured, and the face gear honing experiments are performed. The measurement results of the tooth surface deviations indicate that the maximum deviation decreases from 39.4 to 15.1 μm by amending the processing parameters. The experimental results prove that the honing method is an effective approach to improve the production efficiency of the face gear.

A novel gear machining CNC design and experimental research

Abstract: Strict position and speed synchronization constraint relationship of the gear machine tools axes make gear machining different from the traditional multiaxis machining process. This paper proposes a reconfigurable embedded CNC system platform used for gear machine tools based on the “ARM + DSP” hardware structure. The parametric automatic programming module is introduced to generate NC machining program according to the gear parameters, cutting tool parameters, and machining process parameters automatically. The gear machining process-database module is used to support the previous function modules to optimize the cutting process cycle parameters through intelligent expert knowledge base. In order to meet the requirements of multiaxis synchronous movement, a new type of software electronic gearbox is put forward, and the implementation method of it in the CNC is also studied. To reconfigure the electronic gearbox (EGB) function and simple parameters setting, the embedded gear machining CNC system can be applied to different gear cutting machine tools, such as gear milling, shaping, hobbing, scudding, grinding, and honing machine. Finally, the proposed embedded CNC system is verified experimentally on a six-axis gear hobbing machine. All of the tracking error, contour error, and final measured results show that the proposed CNC system which has these core gear machining function modules can work effectively.

Mutual influence of plateau roughness and groove texture of honed surface on frictional performance of piston ring–liner system:

Abstract: The cylinder liner surface finish, which is commonly produced using the honing technique, is an essential factor of engine performance. The characteristics of the texture features, including the cr...

Effect of applied voltage and electrolyte parameters on pitch, runout, flank topology, and finishing productivity of the straight bevel gears in PECH process

Abstract: This paper describes improvements in the considered parameters of micro-geometry: flank surface topology and finishing productivity of 20MnCr5 alloy steel straight bevel gears through their finishing by pulsed electrochemical honing (PECH) process. Effects of three most important parameters of PECH process, namely applied voltage, electrolyte composition, and electrolyte concentration were investigated to identify their optimum values. Pre-identified values of other PECH parameters and an aqueous mixture of NaCl and NaNO3 as an electrolyte were used in the present work. Errors in pitch (i.e., single pitch error, adjacent pitch error, and cumulative pitch error) and runout were used to evaluate micro-geometry of the straight bevel gears while volumetric material removal rate was used to judge the finishing productivity of the PECH process. Topology of the gear tooth flank surface and microstructure of the best-finished bevel gears were also studied. The results revealed considerable improvements in...

The roughness characterization in cylinders obtained by conventional and flexible honing processes

Abstract: Crankcase cylinders of hermetic compressors are produced in large numbers for refrigerators of domestic use They are, usually, machined by using a three-stage honing process (roughing, semi-finishing, and finishing), and for their characterization during the quality control, an evaluation of roughness is carried out Although the roughness represents a peerless factor to characterize the honed surfaces, its implementation is a challenge for scientists and technicians in general due to the difficulty of detecting the difference between the surface finish on different honing stages This paper assesses the roughness of parts obtained by flexible honing applied after conventional honing process by using a portable surface roughness tester and an interferometer in white light mode (chromatic length aberration—CLA) An extensive evaluation of roughness was made using several roughness parameters, graphics, and curves that include the following: roughness profile, topographies, amplitude parameters, Rk family parameters, volume, and feature parameters The measurement uncertainty associated with all roughness parameters was estimated by applying the methods proposed in the JCGM 101 The results obtained after flexible honing were compared with those found in parts machined by conventional honing This experimentation showed that flexible honing process when applied after the conventional honing provided an essential improvement of the surface finish and an increase of the repeatability and the quality of honed parts The volume and the feature parameters can be used as alternative to appropriately characterizing honed surfaces, because they were able of detecting the changes caused on the surface by different stage of honing process

Wear Characterization of Cemented Carbides (WC–CoNi) Processed by Laser Surface Texturing under Abrasive Machining Conditions

Abstract: Cemented carbides are outstanding engineering materials widely used in quite demanding material removal applications. In this study, laser surface texturing is implemented for enhancing, at the surface level, the intrinsic bulk-like tribological performance of these materials. In this regard, hexagonal pyramids patterned on the cutting surface of a tungsten cemented carbide grade (WC–CoNi) have been successfully introduced by means of laser surface texturing. It simulates the surface topography of conventional honing stones for abrasive application. The laser-produced structure has been tested under abrasive machining conditions with full lubrication. Wear of the structure has been characterized and compared, before and after the abrasive machining test, in terms of changes in geometry aspect and surface integrity. It is found that surface roughness of the machined workpiece was improved by the laser-produced structure. Wear characterization shows that laser treatment did not induce any significant damage to the cemented carbide. During the abrasive machining test, the structure exhibited a high wear resistance. Damage features were only discerned at the contacting surface, whereas geometrical shape of pyramids remained unchanged.

1.4 Review of Gear Finishing Processes

Abstract: Gear is an essential mechanical component whose annual consumption is more than 10 billion. It is used in various automobile, avionics, marine, naval, construction, biomedical and agricultural appliances, machine tools, and in all those applications where the power and/or motion to be transmitted between the two shafts. Type and characteristics of the finishing process significantly affects surface quality, microgeometry, surface integrity, and fatigue behavior of the gears which in turn determine their operating performance, transmission, noise and wear characteristics, and service life. Selection of proper finishing and properties enhancing process for gears greatly helps in optimizing these aspects and helps in optimizing load carrying capacity of the gears. This chapter describes working principle, types, cutting tools used, applications, advantages, and limitations of the most commonly used conventional and some unconventional or advanced finishing processes for different types of gears. The conventional gear finishing processes described are grinding, lapping, honing, shaving, burnishing while advanced gear finishing process include abrasive flow machining (AFM). It concludes with a comparative evaluation of these gear finishing processes which would be very helpful to a user in selecting an appropriate gear finishing process for a particular application.

Formation mechanism study on tooth surface of two gear finishing processes: combined theoretical and experimental approaches

Abstract: As the necessary conditions, high precision and good mechanical performance gear is very important for a high speed and precision transmission system. To meet the requirement of the performance, gear finishing processes including gear honing and gear grinding have been mainly adopted. To compare the tooth surface of these two gear finishing processes, this paper gives the formation mechanism of gear tooth surface texture and conducts some comparative experiments on the gear surface texture and residual stress. Based on the spatial engagement principle and the discrete points of work-piece gear tooth spiral involute surface, the tooth surface contact area models of gears from the two processes are built, respectively, and the prediction models of honing paths and grinding paths are generated according to the velocity vector of the sampling points on tooth surface. Then the contrast and verification tests of the prediction models are carried out on internal gearing power honing machine and worm wheel gear grinding machine, respectively. Results indicate that the predicted curve shape honing paths and the longitudinal linear shape grinding paths of tooth surface are both similar to the experiment ones, respectively. Furthermore, some detailed quantitative analyses of tooth surface qualities including surface texture and tooth surface residual stress has been finished. It is found that the surface roughness value of gear grinding work-piece gear tooth surface is lower than that of gear honing process and the distribution of compressive residual stress on gear tooth surface is associated with the principles and parameters of the two processes. This research has theoretical and instructional significance for the improvement of gear honing and grinding processes.

Topology modification method based on external tooth-skipped gear honing

Abstract: Gears need to be modified in order to meet different application scenarios. Currently, the common method to process the modification is to copy the shape of the modification from grinding wheels or honing wheels to gears, which is less flexible. In this article, a new topology modification method is proposed based on external tooth-skipped gear honing. The new method using the same worm-shaped honing wheel could process different modifications on gears without any modification shape on the wheel. This means no more new dressing wheel for a new modification and thus lower cost. The modification method is demonstrated and compared with other methods to illustrate its characteristics. The control flow of the method is illustrated and the problems in the control are analyzed. Experiments are conducted to verify the feasibility of processing topology modification with this new method.

Study on the frictional performance of slide and plateau honed cylinder liners during running-in

Abstract: Purpose During running-in, the change in the honed cylinder liner surface alters the performance and efficiency of the piston ring-pack system. The present paper, thus, aims to investigate the surface topography and wear and friction evolution of a cylinder liner surface during the running-in tests on a reciprocating ring–liner tribometer under a mixed lubrication regime. After an initial period of rapid wear termed “running-in wear”, a relatively long-term steady-state surface topography can emerge. A numerical model is developed to predict the frictional performance of a piston ring-pack system at the initial and steady-state stages. Design/methodology/approach The liner surfaces are produced by slide honing (SH) and plateau honing (PH). The bearing area parameter (Rk family), commonly used in the automotive industry, is used to quantitatively characterize the surface topography change during the running-in process. A wear volume-sensitive surface roughness parameter, Rktot, is used to show the wear evolution. Findings The experimental results show that a slide-honed surface leads to reduced wear, and it reduces the costly running-in period compared to the plateau-honed surface. The simulation results show that running-in is a beneficial wear process that leads to a reduced friction mean effective pressure at the steady-state. Originality/value To simulate the mixed lubrication performance of a ring–liner system with non-Gaussian roughness, a one-dimensional homogenized mixed lubrication model was established. The real surface topography instead of its statistical properties is taken into account.

Analysis of cavitation orthogonal experiments in power ultrasonic honing

Abstract: Cavitation will occur in the process of power ultrasonic honing. To explore the influence of cavitation on the material surface processed, an ultrasonic honing cavitation orthogonal experiment is conducted and three indicators are analyzed, which are pits’ maximum diameter, surface erosion rate, and surface roughness and can represent the single bubble collapse strength, the whole cavitation strength, and the impact of cavitation on material surface quality, respectively. The results show that cavitation leads to micro-pits on material surface. The main factors influencing the pits’ maximum diameter are distance and amplitude in turn; meanwhile, the shorter distance and the greater amplitude result in the larger pits’ maximum diameter. The surface erosion rate is mainly affected by experiment time and distance in order. Amplitude has the greatest influence on the surface roughness. The sample surface roughness reduces and surface quality improves in the condition of distance of 5 mm, amplitude of 65%, and...

Rotational abrasive finishing (RAF); novel design for micro/nanofinishing

Abstract: Traditional finishing techniques, including grinding, honing, and lapping have several disadvantages and limitations due to their solid and rigid tools with complex geometries. To overcome these limitations, modern techniques known as nanofinishing techniques are introduced. This paper presents a new micro/nanofinishing technique used in different industries, especially high-tech industries like aerospace, military applications, and auto-making industry. This technique is called rotational abrasive finishing (RAF) method. In this technique, the medium inside the cylindrical workpiece is rotated using a bladed stirring axis. The medium hits against the surface of the workpiece while rotating in the opposite direction. In this way, material removal and finishing operation are achieved. In order to avoid medium discharge, two caps, one in upper side and one in the bottom side of workpiece, are used. RAF technique makes it possible to reduce surface roughness and achieve roughness in nanometer scales so that on our test workpiece roughness was reduced from 0.283 to 88 nm, indicating 70% improvement in surface quality by applying 20 min machining duration. It was practically proved that RAF is a fast, efficient, and cost-effective finishing technique for different products by which it is possible to achieve ultra-precise surface quality at nanometeric scales.

Analysis of the Textured Surface of Tangential Turn-Milling

Abstract: Surface texturing is significant for the influence on the functional behavior of contacting parts. Different manufacturing processes like hard-turning, grinding, or honing offer the possibility of accurate surface finishing. Turn-milling seems to be an alternative to apply functional structures on workpieces due to the positive effect of the simultaneous rotary movement of workpiece and tool. The objective of this research was to demonstrate the impact of the process parameters during tangential turn-milling on friction and wear behavior in cylindrical roller bearings in interest of the technical community. Thus, an alternative production sequence with improved tribological performance and reduced resource input was drawn.

Critical review of electrochemical honing (ECH): sustainable and alternative gear finishing process. Part 1: conventional processes and introduction to ECH

Abstract: Surface characteristics of gears affect the various performance characteristics of the gears such as load carrying capacity, service life, operating performance, wear characteristics, transmission characteristics and noise generation characteristics Surface characteristics of a gear have two major components namely (i) surface quality which includes surface finish, micro-geometry (ie form and location errors), tooth flank topology and wear characteristics; and (ii) surface integrity aspects which includes microstructure, microhardness and residual stresses This paper discusses here in Part 1 conventional gear surface finishing processes and their advantages and limitations, and introduces the electrochemical honing (ECH) process to improve the surface characteristics of different types of gears, working principles, mechanism of material removal and equipment details Part 2 will give a review of past work, and discuss effects of various process parameters on surface characteristics and finishing produ

Preparation and Mechanical Properties of Diamond Honing Oilstone

Abstract: The diamond honing oilstone was fabricated by hot-pressing at 550–650 °C and 25 MPa pressure for 4 min, using Cu–Sn based alloys as binder metal and uncoated or W-coated diamond grains as abrasive material. The microstructures and phase compositions of the honing oilstone were examined and analyzed by SEM and XRD. Effects of the oilstone composition, sintering temperature and volume fraction of diamond grains on the mechanical properties of diamond honing oilstone were investigated. The experimental results show that the interfaces between the diamond grains and metal matrices of all the oilstone samples are smooth and no defects are observed in the metal matrices. The bending strength and rockwell hardness of the honing stones increase with the sintering temperature increasing from 550 °C to 650 °C, and the bending strength decrease with the increase of diamond grains faction. The minimum grinding ratio is obtained as the diamond was W-coated, which can be attributed to the improved interfacial bonding derived from the W coating.

Residual stresses induced by honing processes on hardened steel cylinders

Abstract: In the present paper, residual stresses induced by honing processes on hardened steel cylinders were determined. Cubic boron nitride (CBN) abrasives were employed. Both surface measurements and depth profiles were obtained by means of XRD. SEM observations were performed on samples’ surface. Roughness and material removal rate were also measured. Compressive residual stresses, which are known to increase fatigue life of components, were reported both in the axial and in the tangential direction. Shearing stresses were negligible. If only rough honing is taken into account, as a general trend, the lower cutting conditions used, the higher surface stresses are. A similar situation was found when only semifinish or only finish honing is considered. In most cases studied, stress profiles similar to those obtained in grinding processes, in which compressive stresses decrease with depth, were observed. However, in rough honing at hard cutting conditions, a typical hook-shaped profile was found with maximum compressive stress at 80-μm depth. Such shape is usual in turning processes. In order to obtain high surface stresses a rough, semifinish or finish honing operation with low cutting conditions is recommended. However, if stresses are to be obtained at a certain depth, rough honing at high cutting conditions is to be selected.

Neural network modelling of Abbott-Firestone roughness parameters in honing processes

Abstract: In present study, three roughness parameters defined in the Abbott-Firestone or bearing area curve, Rk, Rpk and Rvk, were modelled for rough honing processes by means of artificial neural networks (ANN). Input variables were grain size and density of abrasive, pressure of abrasive stones on the workpiece's surface, tangential or rotation speed of the workpiece and linear speed of the honing head. Two strategies were considered, either use of one network for modelling the three parameters at the same time or use of three networks, one for each parameter. Overall best neural network consists of three networks, one for each roughness parameter, with one hidden layer having 25, nine and five neurons for Rk, Rpk and Rvk respectively. However, use of one network for the three roughness parameters would allow addressing an indirect model. In this case, best solution corresponds to two hidden layers having 26 and 11 neurons.