Abrasive Finishing Process Research Articles

Review of Superfinishing by the Magnetic Abrasive Finishing Process

AbstractRecent developments in the engineering industry have created a demand for advanced materials with superior mechanical properties and high-quality surface finishes. Some of the conventional finishing methods such as lapping, grinding, honing, and polishing are now being replaced by non-conventional finishing processes. Magnetic Abrasive Finishing (MAF) is a non-conventional superfinishing process in which magnetic abrasive particles interact with a magnetic field in the finishing zone to remove materials to achieve very high surface finishing and deburring simultaneously. In this review paper, the working principles, processing parameters, and current limitations for the MAF process are examined via reviewing important work in the literature. Additionally, future developments of the MAF process are discussed.

Optimization of process parameters affecting surface roughness in magnetic abrasive finishing process

ABSTRACTDevelopment in manufacturing technology enhances the mechanical behavior of machined parts and improves the surface finish with high precision, which conveys the progressive importance of magnetic abrasive finishing (MAF) process. In current research work, magnetic abrasive particles were used as finishing tools during the MAF process. However, these magnetic abrasives are fabricated by special techniques, i.e., the adhesive bonding-based method, the sintering method, the plasma-based method and so on. The present study explores the basic finishing characteristics of the magnetic abrasive produced by the sintering process. After the sintering process, improved quality of magnetic abrasives was obtained, where the abrasive particle sticks on the base metal matrix. The abrasive particle used is alumina powder and the magnetic particle is iron powder. Experiments were performed on Stainless Steel 202 to inspect the sound effects of several process parameters such as rotational speed, electromagnet voltage, machining gap and abrasive particle size on machining performance. Apart from that, surface roughness was also measured, which revealed the influence of the abrasive particle on the machined surface in terms of surface finish. It is observed from this study that appropriate size of magnetic abrasive particle optimizes the surface finish.

Investigations on the Finishing Forces in Magnetic Field Assisted Abrasive Finishing of SS316L

Magnetic Field Assisted Abrasive Finishing (MFAAF) process is one of the advanced fine finishing process which uses a flexible multipoint cutting tool to finish the workpiece. The knowledge of finishing forces acting during the MFAAF process is essential to understand the nature of surface finish produced. This paper presents the effect of process parameters like voltage supplied to the electromagnet, machining gap, rotational speed of electromagnet, abrasive size and feed rate on finishing forces during MFAAF process. The work material selected was SS316L material. The experiments were carried out as per Taguchi L27 orthogonal array. Kistler cutting force dynamometer (Model 9257B) and charge amplifier (Model 5070A) were utilised to measure the normal and tangential forces. From the experimental results, it was found that higher voltage (22 V) and lower machining gap (1.5 mm) resulted in maximum magnitude of the normal and tangential forces to 33.92 N and 14.16 N respectively. Also it was observed that the voltage supplied to the electromagnet and the machining gap have significant effect in determining the normal and tangential cutting forces.

Parametric Study in Surface Finishing of Inconel 718 Surface with Magnetic Abrasive Finishing Process

Parametric Study in Surface Finishing of Inconel 718 Surface with Magnetic Abrasive Finishing Process

THE FORMATION OF THE SURFACE DURING AN ABRASIVE FINISHING AT CONSTANT AND VARIABLE CLAMPING FORCES: FINISHING AT CONSTANT AND VARIABLE CLAMPING FORCES

In this work the flat abrasive finishing process is reported. The mechanical and chemical phenomena taking place during the finishing process are described. The most common forming process schemes observed during abrasive treatment are reviewed. The schemes of pulsed, geometrical and energetic models are discussed. On the basis of the energetic hypothesis and Preston hypothesis, the rational law of clamping force variation during the finishing is established. This law allowed for the stabilization of the contact pressure and an increase of the treatment efficiency. An exponential dependence of a boundary contact area variation during the finishing of planes with different initial profiles of the macro-topography is developed. An experimental confirmation of the Preston hypothesis during the abrasive finishing is carried out with the plane-finishing machine “Rastr 220”. The comparison experiments are carried out at constant and variable clamping forces of the treated surface towards the tool. It is found that by varying the forces according to the exponential law (i.e. similar to the changing of the boundary contact area during the abrasive finishing) the process efficiency is increasing by a factor of 2.5–3. It is shown that the changes of the root mean square deviation [Formula: see text] of the roughness [Formula: see text] of a treated surface in the beginning of the process (at time [Formula: see text] min) during the finishing at a constant clamping force is two times higher compared to the treatment at a variable clamping force in the same time period.

Surface roughness modelling for Double Disk Magnetic Abrasive Finishing process

Magnetic Abrasive Finishing (MAF) is a super finishing process having capability to produce surface finish in nano-meter level. The value of surface roughness obtained using MAF process depends upon the material properties of work piece and process factors. In the present work, a mathematical model has been proposed for Double Disk Magnetic Abrasive Finishing (DDMAF) process. DDMAF process is a process that can effectively finish even the flat paramagnetic work piece, which were considered ineffective to be finished by conventional MAF. In the present work, the surface roughness has been modelled as a function of workpiece material properties and process factors namely working gap, abrasive mesh number, percentage weight of abrasive, rotational speed and feed rate. The process model utilizes Lorentz force and Amperes law to estimate the finishing force experienced by an iron particle. The force so obtained has been used to calculate the finishing force transferred to the abrasive particle by using force equilibrium between iron and abrasive particle. The effect of normal distribution of abrasive particle size and the effect of frictional force on finishing forces have also been considered in this work. A MatLab code has been developed to include all the above aspects to determine the change in surface roughness. The model so obtained has been validated using experimental findings and thereafter used to study the effect of various process parameters.

Cleanability of milk deposits on inner stainless steel tubing surfaces prepared by magnetic abrasive finishing

Milk deposits are a serious technical and economic problem for the dairy industry. The proteins and minerals in milk form deposits on the surfaces of stainless steel equipment. The Magnetic Abrasive Finishing (MAF) process was used to produce highly finished inner surfaces of stainless steel tubes to compare to tubes with conventional inner surfaces. Deposition and cleaning tests were carried out using an experimental loop including the stainless steel tubes with different surface roughness profiles. Data showed that the smoothly finished inner surface (Ra = 0.037 μm) of stainless steel tubes prepared by MAF significantly improved the cleanability of milk residues. The results may indicate that the cleanability of non-protein components of milk residue is affected by surface roughness.

Experimental investigations into sintering of magnetic abrasive powder for ultrasonic assisted magnetic abrasive finishing process

ABSTRACTThe importance of magnetic abrasive powder (MAP) in finishing the surface of work materials as a flexible cutting tool in the presence of a magnetic field during the ultrasonic assisted magnetic abrasive finishing (UAMAF) process is quite evident. A sufficiently intense magnetic field provides the desired magnetic force to the iron particles. This holds nonmagnetic abrasive particles firmly and thus makes flexible chains. However, at higher rotational speeds of the magnet due to the requirement of high centripetal force, the chains start flying away from the finishing zone. In the present work, to overcome this deficiency, bonded MAPs were developed using the sintering technique. The effect of various process parameters on the magnetic property (magnetization) of sintered MAPs was investigated. Design of experiments (DoE) was planned as per the L8 orthogonal array of the Taguchi method, and magnetizations along with M-H curves for all eight different MAPs were measured. Subsequently, analysis of experimental data was carried out using various techniques to optimize the process parameters. It was observed that sintering temperature affects magnetization the most. Scanned microscopy (SEM) and X-ray diffraction (XRD) analysis were also carried out to investigate bonding strength in sintered MAP.

A Comprehensive Review on Magnetic Abrasive Finishing Process

In the nanotechnology era, the need for products with high quality and surfaces with free-from damage has become an urgent necessity. Many components in the precision industries such as electronics, automobile, medical, and aviation require high surface finish to meet their functional requirements, such as, reducing fluid flow resistance, friction, optical losses and increase fatigue strength. However, the scale of such surface quality cannot be achieved by traditional finishing methods. To overcome these limitations, many advanced finishing processes have been developed such as abrasive flow finishing, magnetorheological fluid finishing, magnetic float polishing, and chemical mechanical polishing and magnetic abrasive finishing. Magnetic abrasive finishing (MAF) is one of advanced finishing processes which offers superior surface finish over conventional finishing processes, because of its self-adaptability to finish of different geometric shapes, its a gentle tool which does not impact workpiece surface, its capability to polish advanced engineering materials and its low cost. This article has been focused on MAF, as well as reviewing of advanced finishing processes. The recent researches and challenges of MAF have been discussed as well.

Multi-objective optimization of improved magnetic abrasive finishing of multi-curved surfaces made of SUS202 material

Surface roughness is one of the most significant factors that influence the performance of the loss of power and the wear resistance due to friction in engineering. It is difficult to finish simultaneously multi-curved surfaces by conventional finishing process. Besides, this process has to satisfy the criterion of minimum surface defections, accuracy, and high quality surface finish. This study proposes the improved magnetic abrasive finishing (IMAF) in which a magnetic abrasive finishing process was assisted by ring-magnetic field finishing the multi-curved surfaces made of alloy SUS202 in less processing time. The multi-objective particle swarm optimization (MOPSO) algorithm with the knee point (a better solution) was applied to optimize surface roughness of workpiece. The objective functions of the MOPSO depend on the quality of the surface roughness of finishing materials for both simultaneous surfaces (Ra1, Ra2), which are determined from experimental approach. Finally, the effectiveness of the process is compared between the optimal results and the experimental data.

Nanometric surface finishing of typical industrial components by abrasive flow finishing

The evolution of ultra precision finishing processes due to the continuous demand of stringent functional and technological requirement of the components has led to the emergence and development of the non-conventional abrasive flow finishing (AFF) process. This could be attributed to the need for relaxation of tool limitations: precise finishing of complex geometries and internal passages in typical industrial components. Herein, the abrasive laden polymer conforms onto the work piece geometry due to its flow characteristics overcoming the shape limitations inherent in conventional finishing processes. The paper describes nanometric surface finishing of typical prosthetic implants and an extrusion die used in bio-medical and pharmaceutical industries, respectively. Finishing and deburring of a propeller and a shuttle valve used in aerospace applications are also discussed. The study highlights the possibility of successful extension and implementation of AFF process in simultaneous ultra precision finishing applications of industrial components. The versatility, functional, and stochastic aspect of the developed AFF system in surface finishing of ferrous and non-ferrous components is also emphasized.

Nano-finishing of cylindrical hard steel tubes using rotational abrasive flow finishing (R-AFF) process

Abrasive flow finishing (AFF) process is used to deburr, polish and radius surfaces and edges by flowing a semisolid viscoelastic abrasive medium over the surface to be finished. The AFF process is used in the industries especially in the case of finishing complex internal and external shapes. However, the AFF process is a time-consuming process due to its low finishing rate. Efforts are made by different researchers to improve its finishing rate. Rotational abrasive flow finishing (R-AFF) process is one of such processes where in complete workpiece tooling is externally rotated and the medium reciprocates with the help of hydraulic actuators to improve the finishing rate. In the present study, experiments are conducted on hard steel (AISI 4340) cylindrical tubes at different extrusion pressures, workpiece rotational speed, number of cycles and medium compositions for finding optimum conditions of the same for higher change in out of roundness (ΔOOR) and material removal (MR). In this study, soft styrene-butadiene- and silicone polymer-blended medium is used for finishing. Initially, these hard tubes are ground using internal grinding process. Because of grinding process, the workpiece possesses OOR of about 2.75 μm. Later, these workpieces are finished using R-AFF process and OOR improves to 1.69 μm (i.e. ≈39 % improvement). Overall, the results of R-AFF are encouraging and the experiments have shown that R-AFF has a very promising future for the industries in terms of better finishing.

Experimental Investigations into Nano-finishing of Freeform Surfaces Using Negative Replica of the Knee Joint

To achieve high level of surface finish is a difficult task especially in complex shaped components, 3-D components and components with freeform (or sculptured) surfaces. Knee joint is one of such components which has freeform surfaces. Surface finish is very expensive and time consuming operation. Moreover, surface finish of a knee joint plays a crucial role in its functionality and life expectancy. The range of variation of surface roughness value on the different faces is required to be minimum. With these objectives in view, Rotational - magnetorheological abrasive flow finishing (R-MRAFF) process is being proposed with special tooling to achieve the above said objectives.To have uniform (or minimum variation) surface roughness values on all the four faces, a negative replica of the knee joint has been fabricated as a fixture so that the medium flow velocity is approximately constant throughout the length of the joint. Secondly, pulsating magnetic field is used to create vibrations in the abrasive particles so that the probability of new abrasive particles interacting with the knee joint surface, is high.

182 磁気研磨法によるSUS304ステンレス鋼管内面の超精密仕上げ

182 磁気研磨法によるSUS304ステンレス鋼管内面の超精密仕上げ

Effect of carbon nano tube (CNT) particles in magnetic abrasive finishing of Mg alloy bars

The Magnetic abrasive finishing (MAF) process is a surface finishing technique in which a magnetic field is used to control abrasive particles during surface finishing of a material. Because smooth surfaces are required for general use, the magnetic abrasive finishing process was developed for finishing surfaces. We studied the effect of CNT particles on the surface roughness of a workpiece. Magnesium alloy bars were used as the cylindrical workpiece and were finished using an MAF process at high workpiece revolution speeds of 1000, 5000, 10000 and 25000 rpm; diamond pastes with diameters of 0.5, 1, and 3 μm were used for comparison. The best value for surface roughness was equivalent to treatment at 0.02 μm when 0.01 g of CNT particles was mixed together with the unbonded magnetic abrasive at 25000 rpm for 20 seconds. CNT particles were applied to the finishing process to improve the surface roughness of the material, because they have many advantageous properties such as very high strength, light weight, elasticity, and high thermal and air stability. CNT particles are particularly effective for the improvement of Mg alloy bar surface roughness in the MAF process.

Study of magnetic abrasive finishing in seal ring groove surface operations

Because the seal ring groove is used in conjunction with rubber seals, it needs a higher surface quality. Traditional finishing methods are difficult to implement on its bottom and side synchronization finishing because of the special structure of the seal ring groove, and the finishing efficiency is low. To resolve these problems, a magnetic abrasive finishing (MAF) process has been created. As a non-traditional precise machining process, MAF has many advantages. By utilizing the magnet to generate a magnetic field, the magnetic abrasive particles (MAPs) are bound and formed as a flexible magnetic abrasive brush (MAB) for pressing and finishing the workpiece. The external seal ring groove surface can be polished synchronously in the MAF mechanism. Hence, three types of flux paths with the magnet poles in 45°, 90°, and 180° layout were simulated and compared by ANSYS software. The magnet poles’ arrangement and the magnetic flux density were confirmed using measuring equipment. The synchronous MAF device was developed based on the simulation and detection results. The viscosity of lubricant (the percentage between lubricant and water), the spindle speed, the gap between magnet poles and the bottom of the ring groove (gap 1), and the gap between magnet poles and the sides of the ring groove (gap 2) are selected as study objects. Furthermore, the experimental data has been collected using the orthogonal experimental design, and the experimental data on process parameters have been analyzed to determine the optimal conditions. The finished surface of the ring groove about the bottom or side surface has been detected based on the optimal conditions, and it has been found that the surface roughness from initial Ra4.3 μm decreased to Ra0.6 μm. The 3D surface topography has become more uniform and smoother. The results revealed that the MAF can provide a highly efficient way of obtaining high quality and can operate the external seal ring groove surface synchronously.

Study on finishing characteristics of magnetic abrasive finishing process using low-frequency alternating magnetic field

This paper describes a new ultra-precision magnetic abrasive finishing (MAF) process using alternating magnetic field. The process principle and the finishing characteristics are described. Specifically, the effects of finishing parameters such as cutting fluid, rotational speed of magnetic pole, and current frequency on change in material removal and surface finish are investigated respectively. Experimental results indicate that neat cutting oil is more suitable for this processing, which can obtain higher material removal and smoother finished surface compared with water-soluble cutting fluid and silicone fluid. The finishing force and material removal are gradually increasing with the increase of rotational speed of magnetic pole. It is confirmed that the angle variation of magnetic particles is decreasing with the increase of current frequency, and the few nanometer surface can be acquired in the condition of low frequency.

Experimental investigation of external surface finishing of AISI 440C stainless steel cylinders using the magnetic abrasive finishing process

Magnetic abrasive finishing (MAF) is one of the advanced machining processes implementing the material removal in micro dimensions using the magnetic field force and magnetic abrasive particles (MAPs). In this process, the machining forces are low, the surface defects such as micro-cracks are so small and a desirable smooth surface is obtained. In this paper, the effects of parameters such as working gap, workpiece rotational speed, and the material removal mechanism (injecting the abrasive slurry of SiC and Al2O3, and diamond paste) on the surface roughness has been experimentally investigated in the MAF process on the external surface of the AISI 440C stainless steel cylinders. To do the experiments, a setup was designed and manufactured, and the experiments have been implemented according to the design of experiments (DOE) and the full factorial method. The experimental data were analyzed using the analysis of variance (ANOVA). The experimental data analysis showed that the working gap and the workpiece rotational speed have a significant effect on improving the surface roughness. The obtained surface roughness under the conditions of experimental working gap of 2 mm, the workpiece rotational speed of 355 rpm, using the Al2O3 and SiC abrasive slurry injection, and diamond paste has improved as 20, 30, and 50 %, respectively. The images of scanning electron microscopy (SEM) taken from the workpiece surface texture before and after the process confirm the obtained results.

Experimental investigations into ultrasonic-assisted double-disk magnetic abrasive finishing of two paramagnetic materials

This article evaluates the finishing performance of ultrasonic-assisted double-disk magnetic abrasive finishing process on two paramagnetic materials (copper alloy and stainless steel) with different mechanical properties such as flow stress, hardness, shear modulus, and so on. The finishing experiments were performed based on response surface methodology. The results obtained after finishing have been analyzed to determine the effect of different process parameters such as working gap, rotational speed, and pulse-on time of ultrasonic vibration for both work materials and to study various interaction effects that may significantly affect the finishing performance by the process. The outcome of analysis for the two different work materials has been critically compared to understand the effect of the considered process parameters on the finishing performance of the process based on mechanical properties of the workpiece such as hardness. Furthermore, the scanning electron microscopy and atomic force microscopy were carried on the workpiece surface to understand the possible mechanism of material removal and the surface morphology produced after the finishing process.

Research on the electrolytic-magnetic abrasive finishing of nickel-based superalloy GH4169

Due to stable performance and great hardness of nickel-based superalloy, single magnetic abrasive finishing (MAF) is difficult to polish the nickel-based superalloy workpiece, which makes the grinding efficiency decrease. The effective combination of electrolytic polishing process (EPP) and magnetic abrasive finishing process can improve processing efficiency by reducing the influence of material hardness. In order to verify the feasibility of this method, large numbers of experiments on the electrolytic-magnetic abrasive finishing (EMAF) of nickel-based superalloy GH4169 were carried out. Experimental results show that the EMAF can change the surface component content of workpiece to reduce the material hardness and make the surface roughness value reduce significantly and the surface morphology smoother; the processing efficiency is improved by 50 %.