Papers by Keyword: Diamond Wheel

Abstract: Demand for glass Fresnel lenses is increasing in solar panel manufacture in order to increase power efficiency. Glass lenses are usually moulded using a glass moulding method with tungsten carbide moulds. In this study, large Fresnel lens moulds made of tungsten carbide are tested to be ground by a simultaneous 2-axis (Y, Z) controlled grinding method. The resinoid bonded diamond wheel is trued with a rare metal truer to increase the sharpness of the wheel edge. In the grinding test of the tungsten carbide mould, a form accuracy of less than 0.8 μm P-V and surface roughness of 18 nm Rz are obtained, and it is clarified that the proposed grinding method is useful for Fresnel grinding.

Abstract: Demands of glass Fresnel lens is increasing in solar panel in order to increase power efficiency. Glass lens is usually molded by glass molding method with tungsten carbide molds. In this study, large Fresnel lens molds made of tungsten carbide are tested to be ground by simultaneous 2-axis (Y, Z) controlled grinding method. The resinoid bonded diamond wheel was trued with a rare metal truer to improve the sharpness of the wheel edge. In the grinding test of the tungsten carbide mold, a form accuracy of less than 0.8 μm P-V and surface roughness of 18 nm Rz were obtained, and it is clarified that the proposed grinding method is useful for the Fresnel grinding.

Abstract: SiCp/Al composites were grinded with Diamond Wheel on high-precision machine. Acquiring grinding force signals of the experiment with High Speed Advantech PCI－1712 board. Acquired grinding force signals are analyzed in MATLAB which has mighty function disposing signals. Through analyzing the grinding force in time field, frequency field and the signals wavelet analysis for different grinding parameters, found that the feed velocity has much more influence on the grinding force, the grinding force ratio and the standard variance of the grinding force than the depth of grinding when the velocity of the Diamond Wheel is fixed. The frequency structure and energy distribution of grinding force are showed in PSD analysis. The signals are de-noised in wavelet tools. The result of the experiment indicates the grinding force increases, the grinding force ratio decreases and the standard variance of the grinding force varies complex for different material with the increasing of the velocity of the workpiece and the grinding depth.

Abstract: Dies for injection molded parts require high-quality surface finishes in terms of both appearance and integrity. Manual finishing by skilled workers is required to produce such surfaces, but this takes several days. To minimize the amount of polishing required, a new finishing technique that employs ultrasonically assisted diamond grinding was proposed in a previous report. Cutting edge truncation prior to grinding is required to produce a mirror surface. In this study, the effect of cutting edge truncation was investigated and the relationships between the ground surface roughness and the cutting torque and the thrust force were considered to optimize the grinding conditions for mirror surface finishing.

Abstract: An investigation was undertaken to explore the grinding energy and removal mechanisms in grinding zirconia by using brazed diamond wheels. The grinding forces were measured and the morphological features of ground workpiece surfaces were examined. The results indicate that material removal mechanisms are dominated by the combined removal modes of brittle and ductile. The prevailing removal mechanism for the ground surface of zirconia changes from brittle to ductile when the maximum chip thickness change from large to small.

Abstract: This paper deals with the grinding performances of SiCp/Al composites with higher volume fraction and larger SiC particle. The effects of the grinding parameters on the grinding force, removal mechanisms of SiC particles have been investigated. The grinding tests were carried out by using diamond wheel on surface grinding machine. The results indicate that the feed speed of worktable has more significant effect on the grinding forces than that of grinding depth. The scanning electron microscopic images of the machined surfaces indicate that the material removal of SiC particles was primarily due to the failure of the interface between the reinforcement and matrix, and resulting from microcracks along the interface and many fracture or crushed SiC particles on the ground surface.

Abstract: In this paper, metal-bonded diamond wheels of different sized abrasive grain with different porosity were fabricated. Grinding experiments with these wheels on three kinds of materials were carried out under different grinding conditions. Experimental results revealed that wheel with high porosity (38%) had smaller grinding forces and specific energy than the one with a medium porosity (24%) on grinding G603. However, on grinding harder materials like Red granite or ceramics of Al₂O₃, the wheel with 38% porosity had bigger grinding forces and specific energy than the wheel with 24% porosity. Both wheels exhibited good self-sharpening capability during the grinding process of G603 and Red granite, but on grinding ceramics of Al₂O₃ the wheel with 38% porosity displayed in dull state during the grinding process . With the same porosity, the grinding forces of the wheel with a grain size of 230/270 US mesh were lower than the one with a grain size of W10 when grinding Red granite and ceramics of Al₂O₃. However revising results were obtained on grinding G603.

Abstract: This paper describes the wear behaviors of a resin bond diamond wheel in elliptical ultrasonic assisted grinding (EUAG) of monocrystal sapphire. The EUAG is a new grinding method proposed by the present authors in which an elliptical ultrasonic vibration is imposed on the workpiece by using an elliptical ultrasonic vibrator. In our previous work, an experimental apparatus mainly composed of the vibrator was produced and grinding experiments were conducted involving sapphire workpiece. In this paper, further investigations focusing on the wear behaviors of resin bond diamond wheel in EUAG of sapphire were carried out experimentally. The obtained results showed that: (1) the wheel wear process can be divided to three regions according to the variation trend of grinding forces, i.e., an initial region, a steady region, and a deteriorated region; (2) in the initial and steady regions, the grinding forces and the ratio of the normal grinding force to the tangential grinding force in EUAG are much smaller than that in conventional grinding (CG), but in deteriorated region, the grinding forces in EUAG are increased significantly up to be larger than that in CG whereas the grinding forces ratio has few difference between those in EUAG and CG; (3) in all the regions, the work-surface in EUAG is much smoother than that in CG whereas the wheel wear has little influence on the work-surface roughness; (4) the wheel wear in CG is mainly caused by the attrition wear and the macro-fracture and pullout of abrasive grains, while in EUAG by the micro-fracture and cleavage of abrasive grains.

Abstract: A grain-arranged diamond wheel was developed and grinding performance of the wheel against aluminum alloys and titanium alloy, Ti6Al4V, has been investigated using various kinds of grinding fluid. Mirror finishing of aluminum alloys was successfully performed without grinding burn when emulsion-type grinding fluid with an extreme-pressure additive was used. When oil base lubricants or a fatty acid was supplied using a MQL supply unit, fine finishing could not be done. Mesh size of the grinding wheel had only a minor effect on surface roughness. When Ti6Al4V was ground by the developed wheel, an adhesion of work material on diamond grains occurred causing the finished surface to deteriorate.

Abstract: This paper reports on the wheel wear in high speed grinding silicon nitride used metal bond diamond wheels. The investigation focuses on the relation among grinding force, grinding ratio and wheel wear. Experiments have been performed to investigate the factor of wheel wear such as grinding ratio and grinding force. The results of these investigations are presented in this paper. With the application of this technology, a low cost production and high efficiency of ceramic bearing ring grinding can be realized.