Modern Developments in Magnetic Field Assisted Abrasive Flow Machining Processes

Author(s):  
Palwinder Singh ◽  
2019 ◽  
Vol 20 (6) ◽  
pp. 620 ◽  
Author(s):  
Farhad Najarian ◽  
Roozbeh Alipour ◽  
Abbas Razavykia ◽  
Ali Farokhi Nejad

Drilling is one of the most important machining processes which are currently carried out on fiber-reinforced composites. These composites possess a layered structure and different properties through their thickness. When drilling such structures, internal defects like delamination occur, caused by the drilling forces and their uneven distribution among the plies. The current study investigates the effect of magnetic field on drilling process of basalt/epoxy composite laminate in order to reduce delamination and the thrust force and improve some hole quality parameters i.e. roughness and cylindricity. A comparison is made between the responses for both normal drilling and drilling with applying a magnetic field. For this purpose, after finding the best combinations of normal drilling parameters, magnetic field is applied to the different configurations of solenoids on the setup of the drilling process. The results highlighted that using different magnet solenoids on the top and the bottom of drilling zone reduces the delamination and can obtain better roughness and cylindricity with lower damage.


2013 ◽  
Vol 394 ◽  
pp. 205-210
Author(s):  
A.K.M. Nurul Amin ◽  
Fawaz Mohsen Abdullah ◽  
Ummu Atiqah Khairiyah B. Mohammad ◽  
Muammer Din Arif

Chatter is a self-excited and violent form of vibration which is almost unavoidable in all machining processes. It affects surface roughness, machining accuracy, cutting tool and machine tool life, metal removal rate; and consequently operation cost. This research work focuses on investigation of the influence of the cutting parameters on chatter and implementation of a method based on application of permanent magnet for controlling chatter during turning of stainless steel AISI 304 using coated carbide tool. For this purpose, a powerful permanent bar magnet (of strength 1250-1350 Gauss) was placed inside a specially developed fixture mounted on the lathe machine carriage, to apply magnetic field to the base of the tool holder in the Z direction. The effectiveness of the application of the magnet on chatter suppression was measured in terms of reduction of amplitude of chatter compared to conventional turning. To achieve this, a small central composite design (CCD) of the Response Surface Methodology (RSM) with five levels and an alpha value of 1.4142, was used in the design of the experiments (DoE). Design-Expert 6.0 software was utilized in the model development process. Vibration monitoring was done using an online vibration monitoring system. FFT analysis of the recorded vibration signals was conducted using DASYLab software to evaluate the peak chatter amplitudes and their corresponding excited frequencies. The acceleration amplitude was found to be reduced by a maximum of 73.43% and an average of 31.58% due to the effect of damping on the resonant amplitude offered by the magnetic field created by the permanent magnet.


2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Shilei Ma ◽  
Shiyuan Pei ◽  
Lin Wang ◽  
Hua Xu

Vibrations caused by the imbalance of a rotor are a frequently encountered problem in machining processes. Especially in high-precision finishing, the workpiece quality is strongly related to the vibration of the machine-tool spindle, which is mainly caused by mass imbalance and cannot be completely eliminated in cutting tools with nonaxisymmetrical structures. An imbalance in centrifugal force is generated by rotor rotation and increases rapidly with rotational speed. A novel active online electromagnetic balancing method based on static magnetic-field analysis is proposed, and an active online electromagnetic balancing device (AOEBD) based on this method was developed under these conditions. The magnetic-field distribution and electromagnetic force generated by the device were analyzed by finite-element modeling. The influence on the electromagnetic force of the misalignment between the rotor and the iron core was investigated. Factors influencing the magnetic force of the device were determined, and reasonable reference values were suggested. The critical eccentricity was also provided. Experiments had been done at last, and the experimental results presented a good performance of this kind of balancing device.


Author(s):  
Anant Bhardwaj ◽  
◽  
Krovvidi Srinivas ◽  
Rajiv Chaudhary ◽  
◽  
...  

Magnetic Abrasive Finishing is a significant process for finishing up to the micro-level. However, with the advancement of technology and hybrids like Viscoelastic magnetic abrasive Finishing and Magnetic abrasive Flow machining, it has become a nano finishing process. To improve the finishing process, the researchers have made a Model and tested the feasibility of the wind turbine magnet in Finishing. The Maxwell simulations were done for the cylindrical Specimen of Brass, Steel Aluminum. The simulations results were in accordance with the fact that the proposed wind turbine magnet may be used for the simulations.


Author(s):  
Mehmet Alper Sofuoglu ◽  
Fatih Hayati Çakir

Several methods have been developed in order to improve the traditional machining processes and machining outputs. In this study, the effect of the magnetic field on the turning process was investigated. AISI-4140 was machined with different cutting speeds and magnetic flux density magnitudes. The magnetic field was generated with neodymium magnets. Machining stability, surface roughness, and maximum cutting temperature were measured. Additionally, chip shapes were examined. The machining stability was determined by measuring the vibration amplitude and other vibrational parameters (natural frequency, stiffness, and damping coefficients). Conventional turning and magnetic assisted turning were performed under the same cutting parameters consecutively, and the results were compared. According to the results, it was observed that neodymium magnets attached to the cutting tool improve machining stability and damping properties. Surface roughness was decreased between 6%–10% in magnetic assisted turning. Furthermore, it has been observed that the maximum cutting temperatures have been increased between 10%–45% in the magnetic assisted machining. Besides, it can be said that magnets contribute to improving chip control by collecting the chips on them while machining AISI-4140 steel.


Author(s):  
Premangshu Mukhopadhyay

The process of combining two or more non-conventional machining processes to obtain the required machining performance is known as hybridisation. Hybrid electro discharge machining came into the picture of macro machining due to the requirement of more rapid machining process with improved efficiency of non-conventional machining process. The technique of vibration assisted EDM process did not prove to be successful due to some disadvantages like increase in tool wear for low melting and comparatively softer tool material. Therefore, a need for more advanced hybridised process has been realized to improve the overall machining efficiency specially circularity and radial overcut. A permanent magnetic field force assisted EDM process was carried out on SS 316 plate with tungsten carbide tool of 5 mm diameter. MRR, TWR, and diametral overcut have been optimized by firefly algorithm technique which showed satisfactory results. It has been found that tool wear and diametral overcut has been found to be reduced with magnetic field-assisted EDM than conventional EDM processes.


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