Electrically conductive nanocomposite films deposition and electrical discharge machining of ceramic surfaces to generate functional microtextures

Author(s):  
Marina A. Volosova ◽  
Anna Okunkova ◽  
Sergey V. Fedorov ◽  
Enver Mustafaev ◽  
Khaled Hamdy
2010 ◽  
Vol 126-128 ◽  
pp. 591-596 ◽  
Author(s):  
Manabu Iwai ◽  
Shinichi Ninomiya ◽  
Gaku Sugino ◽  
Kiyoshi Suzuki

A new PCD material named EC-PCD (Electrically conductive polycrystalline composite diamond), which consists of electrically conductive diamond grits, has recently been developed. This paper deals with an investigation of a complex grinding assisted with electrical discharge machining (EDM) to realize high efficiency, low and stable grinding force and low wheel wear for the new EC-PCD. The effect of complex grinding assisted with EDM is compared experimentally with the standard PCD (S-PCD). The result shows that, in the complex grinding, lower and more stable grinding force is realized thanks to the material removal action in EDM and that lower wheel wear and better surface finish are attained, just when the EC-PCD is selected as a workpiece.


Author(s):  
Ali Zahedi ◽  
Jahangir Khosravi ◽  
Bahman Azarhoushang

AbstractSuper abrasive diamond grinding wheels are the most promising tools for the precision machining of advanced ceramics and carbide materials. However, the efficiency of conventional conditioning of these tools is limited owing to high dressing tool wear, long process time, low form flexibility, and induced damage to the abrasive grains. Wire electrical discharge machining (WEDM) is an alternative method for conditioning of superabrasive grinding wheels with electrically conductive bonding materials. In this study, cylindrical plunge grinding of an alumina ceramic with a resin-bonded diamond grinding wheel is investigated. The assigned type of resin bond contains copper particles and is accordingly electrically conductive for wire electrical discharge conditioning (WEDC). Conventional (mechanical) and WEDC methods are used for generating the same profile on two similar diamond grinding wheels. As a result, the specific grinding energy was reduced up to 26% and 29% during rough and finish plunge grinding, respectively. Reduced specific grinding energy and forces, along with more effective grain protrusion and sharpness by using WEDC for profiling of grinding wheels, have contributed positively to the ground surface conditions despite the relatively rougher wheel surface topography in comparison to the conventional profiling. The more considerable reduction in the mean roughness depth (Rz) than in the arithmetical mean roughness value (Ra) (11% smaller Rz values in WEDC versus mechanical conditioning) verifies that the workpiece surface underwent less surface degradation in case of WEDC because of smaller grinding forces. Furthermore, the profile wear behavior of the workpiece ground with the WED conditioned grinding wheel was superior to the conventionally conditioned one.


2021 ◽  
Vol 8 (5) ◽  
pp. 91-95
Author(s):  
Nayan J. Patel

Electrical Discharge Machining is one of the non-conventional machining processes used for electrically conductive material. It is widely used for manufacturing complicated parts which are tough to be produced by conventional manufacturing processes. It is based on thermoelectric energy between workpiece and electrode. Metal is removed by melting and vaporizing because of spark occurs in the gap between electrode and workpiece. Workpiece and electrode must have electrically conductive to generate a spark. The performance of the EDM process is largely depends on the electrode. Electrode is considered as tool in EDM process. Selection of the electrode material plays vital role in the EDM process. Different electrode materials have different properties. Hence, the performance of the EDM process changes with different materials. Researchers have used different materials as electrode to investigate the effects of materials and to improve the performance of EDM process. This paper reviews the research work carried out in the field of materials and manufacturing methods for electrodes in EDM process. Keywords: [EDM, Electrodes, Materials, Manufacturing Process].


2005 ◽  
Vol 492-493 ◽  
pp. 27-32 ◽  
Author(s):  
Dongtao Jiang ◽  
Jef Vleugels ◽  
Omer Van der Biest ◽  
Wei Dong Liu ◽  
Raf Verheyen ◽  
...  

Electrically conductive and wear resistant Si3N4-based composites were developed in order to facilitate electrical discharge machining (EDM). The microstructural and mechanical properties of Si3N4-based composites with different amounts of TiC0.5N0.5, fabricated by hot pressing at 1650°C for 1 hour, are investigated and evaluated. The hardness of the micron-sized TiC0.5N0.5 powder based composites increased with increasing TiC0.5N0.5 content from 20 up to 40 vol. %, whereas the bending strength decreased. The fracture toughness reached a maximum at 30 vol. % TiC0.5N0.5 and exhibits a strong anisotropy with respect to the hot-pressing direction. The EDM behaviour of the composites is strongly influenced by the TiC0.5N0.5 content. The composites with a higher TiC0.5N0.5 content have a lower material removal rate but a better surface quality.


2011 ◽  
Vol 264-265 ◽  
pp. 956-961 ◽  
Author(s):  
Md. Ashikur Rahman Khan ◽  
M.M. Rahman ◽  
M.M. Noor ◽  
K. Kadirgama ◽  
M.A. Maleque

Electrical discharge machining (EDM) technique has been widely used in modern metal working industry for producing complex cavities in dies and moulds, which are otherwise difficult to create by conventional machining. The process has the advantage of being able to machine hardened tool steels. However, its low machining efficiency and poor surface finish restricted its further applications. To address these problems, one relatively new technique used to improve the efficiency and surface finish is EDM in the presence of powder suspended in the dielectric fluid. Powder mixed electric discharge machining (PMEDM) is one of the recent innovations for the enhancement of capabilities of EDM process. In PMEDM, the electrically conductive powder is mixed in the dielectric fluid of EDM, which reduces the insulating strength of the dielectric fluid and increases the spark gap between the tool and workpiece. As a result, the process becomes more stable, thereby, improving the material removal rate (MRR) and surface finish. Moreover, the surface develops high resistance to corrosion and abrasion. This paper presents the current research trends on dry, near dry EDM and review on research carried out in the area of PMEDM.


2005 ◽  
Vol 291-292 ◽  
pp. 63-66 ◽  
Author(s):  
Kiyoshi Suzuki ◽  
Shinichi Ninomiya ◽  
Manabu Iwai ◽  
Y. Tanaka ◽  
Yoshihiko Murakami ◽  
...  

Electro-discharge grinding (hereafter called ED-grinding) was carried out with a trial manufactured metal bond diamond wheel containing electrically conductive diamond grits (hereafter called EC-D-grits-wheel). In this research two effects i.e. removal action of workpiece by electrical discharge machining, and an in-process dressing action of the cutting edges on the grits are expected to take place. The results of ED-grinding with EC-D-grits-wheel (f100mm, SDE120Q80M) on tungsten carbide indicated a significant decrease of 21% in the grinding force, when the set discharge current was increased from 0A to 12A. It was also clarified from the alternative-grinding test with and without an electro-discharge action that stable grinding characteristics along with a reduced grinding force could be achieved in the case of the EC-D-grits-wheel with the electro-discharge action. High-speed camera photographs indicated that a stable discharge condition was achieved.


Author(s):  
Asfana Banu ◽  
Mohammad Yeakub Ali

Electro discharge machining (EDM) process is a non-conventional and non-contact machining operation which is used in industry for high precision products. EDM is known for machining hard and brittle conductivematerials since it can melt any electrically conductive material regardless of its hardness. The workpiece machined by EDM depends on thermal conductivity, electrical resistivity, and melting points of the materials. The tool and the workpiece are adequately both immersed in a dielectric medium, such as, kerosene, deionised water or any other suitable fluid. This paper is reviewed comprehensively on types of EDM operation. A brief discussion is also done on the machining responses and mathematical modelling.


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