Готові списки джерел за темами / Diamond-spark grinding / Статті в журналах

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Статті в журналах з теми "Diamond-spark grinding"

Автор: Grafiati

Опубліковано: 30 травня 2022

Оновлено: 31 травня 2022

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Zhang, Bei, Hong Jun Xu, Yu Can Fu, and Hong Hua Su. "Development of High Performance Monolayer Brazed Diamond Grinding Tool for Ceramics." Advanced Materials Research 135 (October 2010): 388–92. http://dx.doi.org/10.4028/www.scientific.net/amr.135.388.

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This study has developed a new kind of high performance monolayer brazed diamond tool for ceramic grinding. The grit size of the diamond brazed in the grinding wheel surface is 300m, which has never been reported in diamond tools for ceramic precision machining. The experiment has achieved wonderful surface finish of Zirconia workpiece. This does owe to the designed and precision conditioned topography of the new developed grinding wheel. The topography of the grinding wheel before and after dressing has been measured by means of laser triangulation method. Then the Zirconia workpiece has been ground. The obtained Ra value decreases with no spark grinding times and the minimum Ra of the ground surface is 0.11m. The study proved that the brazed large grit diamond tools would realize high efficiency and precision grinding, namely, high performance of ceramic grinding.

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Bączek, Elżbieta. "Technological properties of metallic-diamond tools manufactured by SPS process." Mechanik 91, no. 12 (December 10, 2018): 1140–43. http://dx.doi.org/10.17814/mechanik.2018.12.204.

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This paper presents the results of the technological properties of impregnated diamond tools fabricated via spark plasma sintering (SPS) during the process of grinding and cutting of highpurity oxides ceramics (ZrO2) stabilized with Y2O3 or MgO. As a metal matrix the water atomized tin bronze and steel-based matrix was used. After sintering, an analysis of microstructure was conducted using scanning electron microscopy. The resulting materials were tested for the apparent density determined by Archimedes’ method, Rockwell hardness (scale B), Young’s modulus, as well as for the technological properties. The performance results of obtained diamond composites were compared with commercial diamond wheel fabricated by HP (hot pressing), usually employed in the grinding of ceramics. Results showed that diamond tools based on Cu-Sn and steel, obtained by SPS, may be successfully used as a matrix in the impregnated diamond tools for cutting or grinding of high-purity oxides ceramics.

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Agarwal, Gopal, and Manoj Modi. "Influence of Dielectric Jet Flushing during Electro Discharge Diamond Surface Grinding Process." Advanced Materials Research 652-654 (January 2013): 2187–90. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.2187.

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The influence of dielectric jet flushing during Electro Discharge Diamond Surface Grinding (EDDSG) on Ti-6A-4V has been reported in this paper. The metal bonded diamond grinding wheel is used as electrode in Electro Discharge Diamond Surface Grinding process. In this process mechanical grinding is coupled with electrical spark of electrical discharge machine to take up the advantages associated with hybrid machining process. The important input parameters in this investigation were “duty factor”, “wheel speed (rpm)”, “magnitude of current (ampere)” and its “duration (Ton, micro-second)”. The effects of these parameters on outcomes i.e. material removal rate (MRR) and surface roughness (Ra) are measured. The noticeable enhancements in material removal rate and surface finish have been seen during EDDSG of Ti-6Al-4V with effective jet flushing. The performance of EDDSG with jet flushing and without jet flushing has been compared.

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Golabczak, Andrzej, and Robert Swiecik. "Assessment of Energy Consumption and Internal Stresses in Surface Layer in the Abrasive Electro-Discharge Grinding (AEDG) Process." Defect and Diffusion Forum 334-335 (February 2013): 89–96. http://dx.doi.org/10.4028/www.scientific.net/ddf.334-335.89.

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In this work, results have been presented related to the influence of selected electrical parameters of the AEDG process on the energy consumption and state of the internal stresses in the outer layer at this stage of the process, in comparison with conventional grinding. The basis of this work has been possible by investigations of the deep grinding of surfaces of the titanium alloy Ti6Al4V with the use of a CBN grinding wheel and sintered carbide S20S with using diamond grinding wheel with metallic binding agent. For the comparative evaluation of the conventional grinding and AEDG, measurements of the specific grinding energy, energy of the spark discharge and internal stresses in the surface layer have been used.

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Bączek, Elżbieta, Piotr Putyra, Marcin Podsiadło, and Barbara Staniewicz-Brudnik. "Wear resistance of the diamond-impregnated specimens fabricated using the SPS process." Mechanik 90, no. 8-9 (September 11, 2017): 793–95. http://dx.doi.org/10.17814/mechanik.2017.8-9.116.

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This paper presents the tribological properties of the diamond-impregnated specimens in the grinding process of sandstone materials. Obtained metallic-diamond composites were homogenized in Speed Mixer and sintered by SPS (spark plasma sintering). The matrix was prepared from: Cu-Sn (NAM-40 80/20 containing 20% wt. Sn) and Fe-Cu-Sn powders. After consolidation the diamond-impregnated specimens were tested for density using the hydrostatic method, Rockwell’s hardness using B scale and for wear rate on abrasive sandstone using a testing rig specially designed to simulate the tool application conditions.

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Wang, Hai Bin, Yan Ling Guo, Fei Hu Zhang, and Song Bao Luo. "Dressing Electric Spark Parameters of Cast Iron Agglutinant Abrasion Wheel." Applied Mechanics and Materials 121-126 (October 2011): 1625–29. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.1625.

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The dedicated wheel dresser was used for the aspheric surface curve grinding device Nanosyhs-300. The dresser can deal with diamond wheel of the cast iron binding agent for electric spark reshaping and on-line electrolysis repairing sharp. Discharge parameter on the reshaping accuracy and efficiency was studied in the reshaping processing. Therefore, a group of discharge parameters for emery wheel dressing were obtained.

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Tong, Fu Qiang, Yong Zhang, and Fei Hu Zhang. "Experimental Study on Ultra-Precision ELID Grinding for Concave Spherical Surface of Carbide." Key Engineering Materials 416 (September 2009): 18–22. http://dx.doi.org/10.4028/www.scientific.net/kem.416.18.

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This paper describes the current situation of spherical grinding for carbide material. The experiment of Concave spherical ELID grinding of generating method for carbide is conducted. Because dressing electrode can’t be installed in limited space due to the small space of concave spherical surfaces and carbide material has good conductivity, the workpiece material was used as dressing electrode in the ELID grinding experiment. According to negative effect of spark discharge in the process of grinding to surface roughness, two methods "ELIDⅡ" and "ELID Ⅲ" were designed. Comparing and analyzing the experimental results, it is confirmed preliminary that the spherical error and surface roughness of the workpiece after "ELIDⅡ" grinding were better than those after the "ELID Ⅲ" grinding. The ELID grinding method using micro diamond powder wheel and using carbide workpiece as dressing electrode is an effective way for spherical ultra-precision grinding for carbide.

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Hryniewicz, P., A. Z. Szeri, and S. Jahanmir. "Application of Lubrication Theory to Fluid Flow in Grinding: Part II—Influence of Wheel and Workpiece Roughness." Journal of Tribology 123, no. 1 (September 26, 2000): 101–7. http://dx.doi.org/10.1115/1.1331278.

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The objective of this study is to model fluid flow in grinding with nonporous wheels. While Part I focused on the flow in a simplified smooth geometry, in this part the wheel surface roughness is introduced. The applicability of the modified Reynolds equation for laminar flows between rough surfaces is verified experimentally in terms of the developed hydrodynamic pressure, using a resin-bonded diamond grinding wheel. The experiments were performed under the spark-out condition (i.e., with the wheel just touching the workpiece) and in actual grinding. Agreement between theory and experiment is shown for Re<100, but a significant discrepancy (most likely due to turbulence) is observed for 300<Re<1500.

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Chen, Shun Tong, and Chih Hsien Chang. "Study on Thinning of a Boron-Doped Polycrystalline Diamond Wheel-Tool by Micro Rotary W-EDM Approach." Applied Mechanics and Materials 217-219 (November 2012): 2167–70. http://dx.doi.org/10.4028/www.scientific.net/amm.217-219.2167.

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This study presents a novel approach for using a micro rotary wire Electrical Discharge Machining (micro w-EDM) to thin the grinding-edge of a wheel-tool made from boron-doped polycrystalline composite diamond (PCD). For thinning the PCD, two discharge circuits (a Resistance-Capacitance (RC) circuit and a transistor) were used as power sources to obtain a grinding-edge of less than 10 µm in thickness and high surface quality. The wheel-blank is vertically mounted on a spindle and while rotating is thinned by micro w-EDM along a planned computer numerically controlled path. Experimental results verify that boron-doped PCD can be successfully thinned down to 5 µm in edge-thickness. The study shows it is possible to break (cut) diamonds of 10-µm grain size, leaving smooth surface-exposed diamonds at the cutting edge of the wheel tool. The dimensional and geometrical accuracy of the wheel-tool can be exactly controlled. Raman analysis reveals graphitizing of the PCD caused by local high temperature spark erosion at a peak of 1593 cm-1 in RC discharge circuit machining. The peak at 1332 cm-1 for the transistor circuit method indicates diamond sp3 structure. The surface degenerating layer produced by transistor circuit machining gives a suitably thin grinding edge with exposed diamond grains.

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Hu, Bo, Christopher Lim, Song Lin Ding, M. Zulafif Rahim, Milan Brandt, and John Mo. "Experimental Study of Wheel Rotating Speed Effect on Electrical Discharge Grinding." Applied Mechanics and Materials 697 (November 2014): 275–79. http://dx.doi.org/10.4028/www.scientific.net/amm.697.275.

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Electrical discharge grinding is used to machine polycrystalline diamond layer of cutting tools, which can effectively drill composite/titanium stacks in modern aircraft frames. In the machine, an electrode wheel is rotated to accelerate debris flushing to quickly recover the dielectric fluid between a spark gap. The aim of this study was to investigate the effect of the wheel speed on polycrystalline diamond removal rate for high erosion efficiency. Multiple wheel speeds were applied in a electrical discharge grinding machine under various pulse on-times and the volumetric removal rates were calculated by the precise position feedback of this machine over the time, which was obtained by the electrical waveform of discharges. The experimental results show that the removal rate increases with the wheel speed up to a limit at the low range and then declines at the high range. This indicates that the wheel speed needs to be optimized for high erosion efficiency under various discharge conditions such as different materials and pulse on-times.

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Golabczak, Andrzej, Marcin Golabczak, Andrzej Konstantynowicz, Robert Swiecik, and Marcin Galant. "Modeling and Experimental Investigations of the Surface Layer Temperature of Titanium Alloys during AEDG Processing." Defect and Diffusion Forum 365 (July 2015): 63–70. http://dx.doi.org/10.4028/www.scientific.net/ddf.365.63.

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Observing the latest manufacturing processes, the following tendencies can be noted: the gain of the energetic efficiency and shortening of the processing time with parallel preservation of the dimensions tolerance, shape tolerance and outer layer quality of the processed workpiece. Also the possibilities of gaining efficiency by rising criteria for process parameters are limited. It is mainly observed in the processing of hard machinable materials like titanium alloys or sintered carbides. Problems related to poor machinability were revealed during the final manufacturing processes using abrasive grinding [1,2]. In this work the results which have been presented are related to the influence by selected electrical parameters of the Abrasive Electrodischarge Grinding (AEDG) on the surface layer temperature of machined samples, in comparison to conventional grinding. Also the change in temperature during the AEDG has been depicted. The basis of this work is similar to the investigations of the deep grinding of surfaces of the titanium alloy Ti6Al4V using CBN and a diamond grinding wheel. For the comparative evaluation of the conventional grinding and AEDG, measurements of the specific grinding energy, energy of the spark discharge and internal stresses in the surface layer have been used.

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Strel’chuk, P. M., and M. D. Uzunyan. "The energy intensity analysis of the diamond-spark grinding of the WolKar nanostructural hard alloy." Journal of Superhard Materials 32, no. 1 (February 2010): 50–54. http://dx.doi.org/10.3103/s1063457610010077.

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Singh, Gyanendra Kumar, Vinod Yadava, and Raghuvir Kumar. "Diamond face grinding of WC-Co composite with spark assistance: Experimental study and parameter optimization." International Journal of Precision Engineering and Manufacturing 11, no. 4 (August 2010): 509–18. http://dx.doi.org/10.1007/s12541-010-0059-3.

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Rao, Xiao Shuang, Fei Hu Zhang, and Chen Li. "Effects of Electricity Parameters on Surface Quality of Reaction Bonded Silicon Carbide Ceramic with Electrical Discharge Diamond Grinding." Materials Science Forum 874 (October 2016): 15–21. http://dx.doi.org/10.4028/www.scientific.net/msf.874.15.

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With some conductivity and low grinding affectivity, a hybrid machining process termed electrical discharge diamond grinding (EDDG) is applied to the precision machining of reaction bonded silicon carbide (RB-SiC) ceramic. As there is electrical spark in the hybrid machining process, the electrical parameters are varied to explore their effects on the surface quality of RB-SiC ceramic with EDDG. In this paper, the experiments of different polarity and gap voltage with EEDG were investigated, and the microstructure and surface roughness on the machined surface of RB-SiC ceramic were analyzed. The surface morphology and micro-cracks were examined with a scanning electron microscope, and the surface roughness was measured with a confocal scanning laser microscope. It is found that surface roughness initially increases and then decreases with increase of the gap voltages and is higher with negative polarity than that with positive polarity. The micromorphology Micro-cracks were observed on the surface machined and are outstanding in re-solidified zone with EDDG.

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Yadav, Ravindra Nath, Vinod Yadava, and G. K. Singh. "Modelling and simulation of spark assisted diamond face grinding of tungsten carbide-cobalt composite using ANN." International Journal of Manufacturing Technology and Management 28, no. 1/2/3 (2014): 146. http://dx.doi.org/10.1504/ijmtm.2014.064624.

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Yeakub Ali, Mohammad, Abdus Sabur, and Md Abdul Maleque. "Micro Electro Discharge Machining of Nonconductive Ceramic: The Issue of Spalling." International Journal of Engineering & Technology 7, no. 3.24 (August 10, 2018): 32. http://dx.doi.org/10.14419/ijet.v7i3.24.17297.

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Nonconductive ceramic materials are used in many engineering applications such as car brake, turbine blade, and hip-bone replacement because of its high dimensional accuracy, corrosion and wear resistant, and biocompatibility. These materials are usually processed with diamond grinding and limited laser applications such as cutting, drilling and scribing. Specific shapes and profiles are still difficult and costly to machine using these processes. Electrical discharge machining (EDM), extensively used for various shapes and profiles on conductive materials having minimum electrical conductivity of 0.10 S.cm-1. It is not directly applicable on nonconductive ceramic materials due to its very low electrical conductivity (<10-10 S.cm-1). However, recently EDM is used on nonconductive materials with the aid of assisting electrode to initiate the spark between conductive tool electrode and nonconductive workpiece. The available material removal models of EDM are based on single spark erosion with uniform melting and vaporization of workpiece materials. However, in EDM of nonconductive ceramics, material removal is not uniform because of random spalling due to alternating thermal stress. In addition, it is difficult to create single spark erosion on a nonconductive ceramic workpiece as initial sparks are occurred between tool electrode and assisting electrode attached to workpiece. This paper presents the empirical factor for the estimation of spalling along with melting and vaporization through experimental study. Model of material removal rate as a function of capacitance and voltage are developed in micromachining of nonconductive zirconium oxide (ZrO2) using (R-C) pulse type micro-EDM. The single spark erosion volume is derived from the fundamental principle of melting and vaporization. An empirical correction factor is introduced to compensate random spalling and multi-spark erosion effect.

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Shi, Shao Hua, Pei Qing Ye, and Chen Xi Fang. "Design of Five-aixs CNC System for Electric Discharge Grinding (EDG) Polycrystalline Diamond (PCD) Tools." Advanced Materials Research 538-541 (June 2012): 1316–21. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1316.

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Polycrystalline Diamond (PCD) tools are widely used while machining wood-based composites because of its outstanding hardness, thermal conductivity and abrasive resistance. However, the above mentioned beneficial properties such as super hardness also cause problems in manufacturing PCD tools using traditional process methods. The main problem now in manufacturing PCD tools is the low efficiency and difficulties while manufacturing PCD tools with complex curved surface. To manufacture PCD tools with complex curved surface more efficiently, in this paper, the mechanical structure, hardware circuit and software system of five-axis EDG CNC system are introduced. To satisfy the unique requirements of EDG, a proper mechanical structure of 5 CNC controlled axis and 2 manual axis are given, as well as the design of hardware circuit of EDG based on PCI Bus. The software system which is designed based on RT-Linux is divided into four modules: real-time cyclical tasks module, real-time gusty tasks module, non real-time tasks module and EDG process database. , This paper gives out the solutions of the specific functions of this special CNC system, including automatic measurement, automatic programming, automatic electrode wear compensation, and detection and control of spark gap. The detailed structure and organization of the software system is also provided. At last, through actual cutting experiments of woodworking PCD tools, the correctness and practicality of this system is verified.

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Oglezneva, S. A., K. L. Saenkov, and A. A. Knyazev. "Study of the effect of dispersion and homogeneity of the structure on the properties of powder metastable austenitic carbide steels and diamond tools." Izvestiya Vuzov. Poroshkovaya Metallurgiya i Funktsional’nye Pokrytiya (Universitiesʹ Proceedings. Powder Metallurgy аnd Functional Coatings), no. 1 (March 21, 2019): 52–60. http://dx.doi.org/10.17073/1997-308x-2019-1-52-60.

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Diffusion and homogenization in powder systems of varying degrees of dispersion «iron (5 μm) – nickel (5 μm or 50 nm)» during sintering (900 and 1000 °C), as well as spark plasma sintering using the Matano-Boltzmann method were studied. In these systems, the calculated diffusion coefficients in pairs of micron powders, sintered without application of pressure (900 °C, 6 h) and the spark plasma method (900 °C, 5 min), were equal to 7·10–10 cm2/s. It is shown that in diffusion pairs based on microdispersed iron powder, the use of nanodispersed nickel powder instead of microdispersed one contributes to an increase in the diffusion coefficient at a temperature of 900 °C by a factor of 2. The constants in the sintering kinetics equation of V.A. Ivensen are calculated for iron–nickel powder systems. Through them the factors activating the sintering of these systems were established. The dependences of the structure-phase composition and physicomechanical properties of carbides of the Fe (base) system — 14 wt.% Ni – 8 wt.% TiC system on the sintering temperature in the interval t = 900÷1200 °C, dispersion and homogeneity of the structure were determined. The dependences of grain size, porosity, hardness, microhardness, toughness, bending strength on sintering temperature are shown. The established dependences of the tribotechnical properties on the degree of homogeneity of the solid solution and the volume of the phase transformation of the metastable austenite to deformation martensite during friction on the abrasive were similar for carbide steels and diamond tools based on carbide steels. The optimal values of the coefficient of variation of nickel concentration in austenite in carbidostils of the same chemical composition, but different dispersion, providing the maximum amount of austenite decomposition and high values of the diamond tool grinding coefficient were 5 in both systems, but the sintering parameters differed. It is shown that the physicomechanical properties of the studied systems depend on the porosity and dispersion of the structure, and the tribotechnical properties are subjected to the homogeneity of the structure of the steel.

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Sakamoto, Haruhisa, and Shinji Shimizu. "Generation Process of Cutting-Edge Distribution on Grinding Wheel with Single-Point Diamond Dressing." Advanced Materials Research 126-128 (August 2010): 1001–6. http://dx.doi.org/10.4028/www.scientific.net/amr.126-128.1001.

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The grinding should be improved to be the skill-free process executed based on the quantified criteria. In this study, the evaluation methods are applied to evaluate the dressing process to clarify how the dressing changes the cutting-edge distribution. From the results, the following facts have been clarified: There is the critical value of the depth of cut for suppressing the release of grain. The spark-out in dressing releases grains damaged by collision with dresser, and then, it also increases the cutting-edge density.

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Liu, Jiangwen, Qinming Huang, Ming Wu, Zhixiang Zou, Zhibiao Lin, Zhongning Guo, Junfeng He, and Xiaolei Chen. "Electrochemical Discharge Grinding of Metal Matrix Composites Using Shaped Abrasive Tools Formed by Sintered Bronze/diamond." Science and Engineering of Composite Materials 27, no. 1 (November 3, 2020): 346–58. http://dx.doi.org/10.1515/secm-2020-0038.

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AbstractElectrochemical discharge machining (ECDM) is a well-known process for machining of particulate reinforced metal matrix composites (MMCs). However, ECDM process suffers several drawbacks such as the lower material removal rate (MRR), high risks of tool wear rate (TWR) and relatively poor surface quality, etc. This study proposes a kind of electrochemical discharge grinding machining (ECDGM) method which employs a special shaped tool electrode. During the process, not only the can the hybrid action of electrochemical dissolution, spark erosion, and abrasive grinding improve the performance of machining MMCs, but also the special shaped of the tool electrode can be used to discharge the machined debris. And thus a higher machining efficiency and lower TWR can be obtained. The performance of developed process was conducted on machining of SiC particulate reinforced aluminum workpiece. The role of peak curre+nt, pulse duration, duty cycle, rotary speed and abrasive grit size has been investigated on MMR and TWR using the nonabrasive round electrode, abrasive round electrode, and abrasive shaped electrode respectively. The experimental results showed that using the shaped abrasive electrode for machining MMCs can achieve a higher MRR and lower TWR, as compared to the non-abrasive round electrode, abrasive round electrode. Besides, the orthogonal method was employed to analyze the relative importance of the machining parameters on MRR and TWR, it has been observed that MRR is affected by the processing parameters following the order of rotary speed > peak current > duty cycle > pulse duration, and TWR is following the order of peak current > duty cycle > pulse duration > rotary speed.

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