Abrasive Finishing Process Research Articles

Development of a New Finishing Process Combining a Fixed Abrasive Polishing with Magnetic Abrasive Finishing Process

High quality, highly efficient finishing processes are required for finishing difficult-to-machine materials. Magnetic abrasive finishing (MAF) process is a finishing method that can obtain a high accuracy surface using fine magnetic particles and abrasive particles, but has poor finishing efficiency. On the contrary, fixed abrasive polishing (FAP) is a polishing process can obtain high material removal efficiency but often cannot provide a high-quality surface at the nano-scale. Therefore, this work proposes a new finishing process, which combines the magnetic abrasive finishing process and the fixed abrasive polishing process (MAF-FAP). To verify the proposed methodology, a finishing device was developed and finishing experiments on alumina ceramic plates were performed. Furthermore, the mechanism of the MAF-FAP process was investigated. In addition, the influence of process parameters on finishing characteristics is discussed. According to the experimental results, this process can achieve high-efficiency finishing of brittle hard materials (alumina ceramics) and can obtain nano-scale surfaces. The surface roughness of the alumina ceramic plate is improved from 202.11 nm Ra to 3.67 nm Ra within 30 min.

Application of response surface methodology to investigate nano-finishing of the silicon wafer

The aim of this research is study the effect of polishing factors to the reduction ratio rate in surface roughness (%[Formula: see text] during the Magnetic Abrasive Finishing (MAF) process using Response Surface Methodology (RSM). The parameters studied were machining gap, rotational speed, abrasive size and magnetic abrasive particle (MAP) size. Quadratic models were developed by applying Box–Behnken Design (BBD). Also, experiments were carried out on the silicon wafer and results of surface roughness data were analyzed by using analysis of variance (ANOVA) and significant factors were identified. According to our findings, the maximum %[Formula: see text] value and the best surface roughness of silicon wafer achieved 3.70 and 51 nm, respectively.

Study on the magnetic abrasive finishing process using alternating magnetic field—discussion on the influence of current waveform variation

With the development of semiconductors, optics, aerospace, and other fields, the requirements for surface finish are constantly increasing. This requires not only better surface quality but also higher finishing efficiency. In order to improve the surface quality, the magnetic abrasive finishing process using an alternating magnetic field was proposed in the previous research. In this process, the magnetic clusters constantly fluctuate due to the periodic change of the current, thereby realizing the circulation of the abrasive particles in contact with the workpiece. It has been proved through previous studies that a better surface quality can be obtained in an alternating magnetic field. However, there are still some unclear mechanisms. For example, the fluctuation of magnetic cluster mainly depends on the change of current, but it is not clear which current change mode is more suitable for improving finishing efficiency and surface quality. Therefore, in this study, the influence of the current change mode on the magnetic field, finishing force, and finishing characteristics are discussed. Furthermore, SUS304 stainless steel plate was used as the object to conduct a series of experiments. According to the experimental results, when the abrasive particles are WA#8000, the average diameter of the magnetic particles is 75 μm, and the frequency is 1 Hz; in the case of pulse current with a duty cycle of 80%, a higher material removal rate can be achieved. The material removal rate is 1.7 times that of the static magnetic field and 1.45 times that of the sinusoidal alternating magnetic field.

A Review on Experimental Investigation of Magnetic Abrasive Finishing process

Magnetic Abrasive Finishing (MAF) is one of the superfinishing processes that produce nanoscale finishing for both metals and non-metals. Also, the MAF process can be utilized for the finishing of magnetic and non-magnetic materials. The basic mechanism of the MAF process consists of a flexible magnetic abrasive brush (FMAB) is developed using magnetic particles and abrasives. The FMAB acts as a multipoint cutting tool and removes material with the application of indentation and shearing action of abrasives. The literature suggests that the concept of surface finish (SF) and material removal rate (MRR) in MAF is limited to only a few materials. However, the phenomena involved in this process must be studied to improve the process mechanism and surface finish capabilities. In this review paper, the concept of surface finish mechanisms using MAF has been revised to date, the possibility of future research has been named and talked over. Attempts to improve the surface finish of MAF are also talked about.

On colors of stainless-steel surfaces polished with magnetic abrasives

Multiple colors visible to the naked eye across the internal surfaces of stainless-steel 304 tubes polished with a magnetic abrasive finishing (MAF) process were investigated at varying levels of magnification. The colors were found to result from microscopic colored features of four different hues — green, blue, red, and yellow — having irregular sizes and shapes. Spectral analysis of their dispersion indicates that these colored features appear along the lay marks generated during MAF. Surface characterization employing energy dispersive spectroscopy and instrumented indentation testing indicates the presence of films of non-stochiometric chromium oxide and nickel oxide in the colored regions. Variations in the momentum and the density of the abrasive particles interacting with the surface during the MAF process, together with the chemical composition and morphology of the surface, provide thermodynamic conditions favorable for a non-uniform growth of the oxides film. Local color is dependent on the local composition and thickness of the oxides film.

Multi-objective optimization of magnetic abrasive finishing using grey relational analysis

The effect of numerous process variables has been explored for surface roughness and material removal rate during the magnetic abrasive finishing process. A hybrid approach was used in which the Taguchi technique is used in conjunction with grey relational analysis to reach the optimum combination of input variables. The L16 orthogonal array design was used to get a different combination of parameters. It was found that spindle speed of 200 rpm, the quantity of magnetic abrasives of 5 mg, mesh number of 270, and machining time 60 min caused minimum surface roughness of 0.066 µm during magnetic abrasive finishing of the brass plate. The percentage contribution of input parameters has been reported. Subsequently, the optimum results were obtained using multi-objective optimization techniques of grey relational analysis, and results were also validated using experimentation.

Optimal parameters of abrasive flow finishing for hip joint implants

Total hip arthroplasty (THA) is one of the most well-known orthopedic surgeries in the world which involves the substitution of the natural hip joint by prostheses. In this process, the surface roughness of the femoral head plays a pivotal role in the performance of hip joint implants. In this regard, the nano-finishing of the femoral head of the hip joint implants to achieve a uniform surface roughness with the lowest standard deviation is a major challenge in the conventional and advanced finishing processes. In the present study, the inverse replica fixture technique was used for automatic finishing in the abrasive flow finishing (AFF) process. For this aim, an experimental setup of the AFF process was designed and fabricated. After the tests, experimental data were modeled and optimized to achieve the minimum surface roughness in the ASTM F138 (SS 316L) femoral head of the hip joint through the use of response surface methodology (RSM). The results confirmed uniform surface roughness up to the range of 0.0203 µm with a minimum standard deviation of 0.00224 for the femoral head. Moreover, the spherical shape deviation of the femoral head was achieved in the range of 7 µm. The RSM results showed a 99.71% improvement in the femoral head surface roughness (0.0007) µm under the optimized condition involving the extrusion pressure of 9.10 MPa, the number of finishing cycles of 95, and SiC abrasive mesh number of 1000.

Tri-objective constrained optimization of pulsating DC sourced magnetic abrasive finishing process parameters using artificial neural network and genetic algorithm

ABSTRACT Owing to the exceptional mechanical properties of Ti-6Al-4V, it is widely utilized in numerous critical mechanical parts for the uncompromised factor of safety. However, performing machining operations on this alloy in close tolerance is a challenging task. Moreover, establishing a process for its efficient finishing has become the interest of researchers. In this research study, the magnetic abrasive finishing process (MAF) has been studied using the ANN-GA approach, where ANN has been used for modeling of input–output relations, and GA has been used to optimize the MAF process. The experiments were conducted on a pulsating DC sourced MAF set-up, and SiC-based loosely bonded magnetic abrasive media was used for material removal. During experimentation, the current, machining gap, speed of rotation, abrasive composition, and finishing time were taken as input parameters being arranged in an array of L16 orthogonal. In contrast, output parameters were changed in surface roughness, change in the microhardness, and change in the modulus of elastic indentation. ANN-GA approach provides a set of optimal solutions for obtaining suitable output values. Furthermore, loosely bound SiC-based magnetic abrasive media and its composition is found to be a very critical factor for the performance of the finishing quality on Ti-6Al-4 V.

Effect of Magnetic Abrasive Finishing on the Corrosion Behavior by Agricultural Pesticides Corrosive Media

This study investigates the effects of surface quality obtained by Magnetic Abrasive Finishing process (MAF) on the amount of chemical corrosion created by agricultural pesticides. MAF is a relatively new method of finishing which uses a magnetic field to control the abrasive tools. In this study, samples from two types of AISI304 stainless steel and brass 6337 were finished with silicon carbide abrasives having various meshes at three different levels of surface roughness as compared to the control part; the first level was rougher than the control part (400 mesh) and the other two levels were smoother from the control part (Mesh 800 and 1200). The migration rate of metal ions was measured to determine the corrosion rate of samples in terms of ppm by the atomic absorption device in two corrosive environments consisting of Paraquat and Deltamethrin pesticides. The results indicate that, when both pesticides are used, reducing the surface roughness improves the corrosion resistance of samples. In summary, the samples finished with 1200 mesh had the best improvement in increasing the corrosion resistance in both steel and brass (36.11% and 34.85%), respectively. The finished samples with 800 meshes also increased corrosion resistance of AISI 304 and brass 6337 up to 20.54% and 15.72%, respectively. It was also found that the corrosion rate of Paraquat solution was about 4.68 times higher than that of Deltamethrin in the same concentration for both of the working materials. The corrosion rate of brass was also higher than that of steel.

Experimental investigation into nano-finishing of β-TNTZ alloy using magnetorheological fluid magnetic abrasive finishing process for orthopedic applications

This study describes the effect of magnetorheological fluid assisted magnetic abrasive finishing (MRAF) process on the surface topography of fine finished high strength biomedical grade β-phase Ti–Nb–Ta–Zr (β-TNTZ) alloy for orthopedic applications. β-type Ti–35Nb–7Ta–5Zr alloy exhibit high strength, better corrosion resistance and excellent bioactivity in comparison with Ti–6Al–4V alloy. The topographic features of finished surfaces (including surface roughness, skewness, and kurtosis), percentage change in surface roughness, and material removal have been studied to understand the influence of MRAF processing parameters, such as carbonyl iron particles proportion, diamond abrasive particles proportion, rotational speed of the abrasive tool, and work gap between workpiece and abrasive tool. Furthermore, MRAF finishing has been conducted using raster and spiral strategies. The topographic characteristics of the finished surfaces have been measured using a noncontact three-dimensional Surface Profilometer and atomic force microscopy. The results of the study showed that all the input process parameters have strongly influenced the surface characteristics in both quantitative (material removal) and qualitative measures (Surface roughness). The β-TNTZ have possed excellent bio-mechanical properties such as high compressive strength (1195 MPa), micro-hardness (515 HV), corrosion resistance, and excellent bioactivity. The best optimal condition to obtain lowest SR (9 nm) and highest MR (65 mg) was obtained in the case of rater path finishing strategy at CIP – 40%vol., Dv – 3.5%vol., Nt – 900 rpm, and Gp – 1 mm. The maximum percentage change in surface roughness (%ΔRa) was measured around 97.68% and 93.27% in raster and spiral path strategy, respectively. The minimum surface finish ranging about 9 nm has been achieved through the MRAF process. Further, the raster path strategy has been found more effective in producing negative skewness (Ssk), kurtosis (Sku) value less than 3, and minimum number of peaks density (Spd). The overall results of the study suggested that MRAF of β-TNTZ alloy is a good solution for obtaining fine-finished orthopedic devices while sustaining their tribological and wear properties.

Effect of abrasive particle morphology along with other influencing parameters in magnetic abrasive finishing process

Surface characteristics play a very important role in medical implants and among surface features, surface roughness is very effective in some medical applications. Among the various methods used to improve surface roughness, magnetic abrasive finishing (MAF) process has been widely used in medical engineering. In this study, the effect of abrasive particle morphology along with four other process parameters, including type of work metal, finishing time, speed of finishing operation, and the type of abrasive powder were experimentally evaluated. Full factorial technique was used for design of experiment. Three commonly used metals in orthopedic implants i.e., Ti-6Al-4V alloy, AZ31 alloy and austenitic stainless-steel 316LVM, were selected for this study. Also, two types of magnetic abrasive particles with different shapes (spherical and rod-shaped) were considered in the experiments. The results of the experiments indicated that the morphology of the abrasive particles and the finishing time had the greatest effect on surface roughness and using rod-shaped abrasive particles resulted in better surface quality comparing to the spherical particles. Besides, the surface quality of steel 316LVM after MAF was the best among the other examined metals. Interaction plots of ANOVA also showed that interactions of material with morphology of abrasive particles, and material with machining time were found to be reasonably significant.

Investigation on the Improvement of Surface Quality by the Magnetic Plate-Assisted Magnetic Abrasive Finishing Process

The traditional magnetic abrasive finishing (MAF) process, the magnetic flux density at the bottom of the magnetic pole is unevenly distributed, resulting in poor uniformity of the finished surface. Therefore, it is proposed to improve the surface quality by attaching a magnetic plate at the bottom of the workpiece to improve the magnetic field distribution. It is confirmed by simulation that the magnetic field distribution at the bottom of the magnetic pole is effectively improved after the magnetic plate is attached. It is proved through experiments that the magnetic plate-assisted MAF process can obtain a smoother surface. The experimental results show that the surface roughness of the glass lens improves from 246 nm Ra to 3 nm Ra through the magnetic plate-assisted MAF process within 45min.

Study on the Magnetic Abrasive Finishing Process Using an Alternating Magnetic Field - Discussion on the Application of Full-Wave Rectifier Current -

To further improve the finishing efficiency, it has been proposed to apply full-wave rectified current to the coil. In this paper, the effect of full-wave rectified current on the magnetic field and finishing force is studied. The effects of full-wave rectified current and alternating current on finishing characteristics were compared through experiments. The experimental results show that, with different magnetic particle sizes, the finishing efficiency shows different results. In the case of full-wave rectified current, when the average diameter of the magnetic particles is 30 μm, 75 μm and 149 μm, the finishing efficiency is higher than the alternating current, and when the average diameter of the magnetic particles is 330 μm, the finishing efficiency is lower than the alternating current.

Investigation on surface finishing of polychlorotrifluoroethylene resin by the magnetic abrasive finishing process using alternating magnetic field

Investigation on surface finishing of polychlorotrifluoroethylene resin by the magnetic abrasive finishing process using alternating magnetic field

Exploration of Desirability Function Analysis-Based Particle Swarm Optimization for Magnetic Abrasive Finishing of Mild Steel

Analysis of surface roughness, temperature and hardness of the finished surface is beneficial to retain the desired surface finish of the workpiece via the magnetic abrasive finishing (MAF) process. In this work, “change in roughness” ([Formula: see text]Ra), “raise in temperature” ([Formula: see text]) and “change in hardness” ([Formula: see text]) were opted for the multi-objective meta-heuristic optimization to minimize their impact on the finished surface of mild steel. Taguchi [Formula: see text] orthogonal array was used to obtain the experimental data on mild steel. The desirability fitness function (DFF) was developed to convert multi-responses to a single response. Finally, particle swarm optimization (PSO) was used for a higher-level decision-making and a meta-heuristic optimization approach, i.e. desirability function analysis-based PSO (PSO-DFA), was developed to obtain the best performance condition for surface finish. The best optimal setting obtained by using PSO-DFA included a working gap of 1.5[Formula: see text]mm, an abrasive weight of 15[Formula: see text]g, a voltage of 6[Formula: see text]V and a rotational speed of 50[Formula: see text]rpm. This setting has been selected based on the highest PSO-DFA value predicted by the meta-heuristic optimization approach and improved by 38.20% in comparison with DFA, that shows a satisfactory performance.

On the temperature analysis of magnetic abrasive finishing of aluminum 6060 using finite element method

Magnetic abrasive finishing (MAF) process is the superfinishing process used to enhance the surface quality of metallic and nonmetallic materials such as alloys, composites and ceramics etc. This process erodes material from a workpiece surface in the form of micro-chips with the help of flexible magnetic abrasive brush (FMAB) in working gap with the presence of a magnetic field. This process generates heat due to rubbing action that produced by FMAB between the interface surface of FMAB-workpiece. Thermal stability of the finishing surface of workpiece is vital during finishing of MAF process because it affects the surface texture and surface integrity. Measuring surface temperature at the interface of FMAB-workpiece during finishing is very tough in MAF process. In the present study, finite element analysis (FEA) is used for simulation of magnetic flux distribution and surface temperature distribution of interface surface of aluminum 6060 workpiece-FMAB of MAF process. FEA predicts the magnetic flux density in between 0.429 T and 1.263 T for current between 3.0 A and 6.0 A) and surface temperature distribution in the range of 27.33 ºC–34.92 ºC for different processing conditions of process parameters. FEA simulated results are validated by comparing with experimental finding and estimated error between simulated and experimental results are in the range of 4.94%–10.26%. Finally, the present developed FEA is employed on the mild steel workpiece to cross-examine the simulated behavior of magnetic flux density and surface temperature at the finished interface surface of mild steel.

Investigation of Finishing Aluminum Alloy A5052 Using the Magnetic Abrasive Finishing Combined with Electrolytic Process

The magnetic abrasive finishing combined with electrolytic (EMAF) process was proposed to improve the finishing efficiency of the traditional magnetic abrasive finishing (MAF) process. Since the EMAF process contains electrolysis reactions, the machining mechanism of processing different metal is different. In this paper, a series of experiments were conducted to explore the feasibility of using the compound processing tool to finish aluminum alloy A5052, and to preliminary explore the machining mechanism. Surface roughness and material removal are used to evaluate the finishing effect and the finishing efficiency, respectively. The EMAF processing current curve is used to evaluate and analyze the EMAF process. The feasibility of the EMAF processing is proved by the analysis of simulations and the experimental results. Finally, through a series of exploration experiments and parameter optimization experiments, the main conclusions are as follows: (1) Compared with the traditional MAF process, when finishing the surface of aluminum alloy A5052 by the same compound processing tool and at the same experimental conditions (except the electrolysis conditions), the EMAF process, which includes electrolysis reactions, can achieve higher finishing efficiency. (2) In this study, when the working gap is 1 mm and the concentration of NaNO3 solution is 15%, the recommended processing voltage is about 3.4 V.

Investigation on Finishing Characteristics of Magnetic Abrasive Finishing Process Using an Alternating Magnetic Field

The magnetic abrasive finishing (MAF) process is an ultra-precision surface finishing process. In order to further improve the finishing efficiency and surface quality, the MAF process using an alternating magnetic field was proposed in the previous research, and it was proven that the alternating magnetic field has advantages compared with the static magnetic field. In order to further develop the process, this study investigated the effect on finishing characteristics when the alternating current waveform is a square wave. The difference between the fluctuation behavior of the magnetic cluster in two alternating magnetic fields (sine wave and square wave) is observed and analyzed. Through analysis, it can be concluded that the use of a square wave can make the magnetic cluster fluctuate faster, and as the size of the magnetic particles decreases, the difference between the magnetic cluster fluctuation speed of the two waveforms is greater. The experimental results show that the surface roughness of SUS304 stainless steel plate improves from 328 nm Ra to 14 nm Ra within 40 min.

Theoretical analysis of technological possibilities of reducing surface roughness at abrasive processing

The paper presents analytical dependences for determining the parameters of surface roughness at abrasive machining with cutting grains positioned spherically at the same height on the working surface of the tool and overlapping mutually in the process of forming the roughness of the processed surface. The calculations established that, provided that the cutting grains are located at the same height on the working surface of the tool as applied to the free abrasive finishing process, it becomes possible to significantly reduce the surface roughness parameters Ra and Rmax. The calculations also stated that these parameters are the less, the less the granularity of the abrasive or diamond grains is at processing. With an increase in the grain size of the diamond powder, in order to achieve the specified values of the surface roughness parameters Ra and Rmax, it is necessary to increase the number of the cutting grains forming the surface roughness. However, this leads to reduced processing performance. It has also been shown that it is not possible to put into practice the processing conditions under which the surface roughness parameters Ra and Rmax, established theoretically, become very small due to the difficulty of providing the same arrangement of abrasive grains on the working surface of the tool. Based on the theoretical solutions obtained, specific practical recommendations have been developed to reduce the surface roughness. So, an effective method of internal grinding has been developed using a soft felt (felt) wheel with a glued layer of abrasive powder 63C. This method can significantly reduce the surface roughness parameter Ra without increasing the complexity and reducing processing productivity. For its practical implementation, it is proposed to use abrasive powder with granularity F80-F150. In doing so, it is effective to grind by setting the axis of rotation of the grinding wheel with an individual drive perpendicular to the axis of rotation of the hole being machined. As a result, the number of simultaneously working abrasive grains significantly increases as compared to conventional internal grinding due to an increase in the contact area of the grinding wheel with the workpiece. Also, a certain different-height arrangement of cutting grains on the working surface of the tool, which takes place under real processing conditions, also decreases, which results in a decrease in the roughness of the machined surface

Study the effect of concentration ratio (magnetic abrasive powder and castor oil) in magnetic abrasive finishing process

The new technology can however be incorporated in conventional machine tools in order to minimize cost of new equipment. In present work, the effect of magnetic abrasive powder and castor oil mixture in magnetic abrasive finishing process is investigated. The lower concentration of lubricating oil results in higher heat accumulation which further decreased the cutting efficiency due to blunting action of abrasives. On the other hand, the larger quantity of lubricating oil prevents blunting which resulted in higher cutting efficiency.