Advanced Materials Research Vols. 24-25

Abstract: The grinding process of aluminum alloy is introduced in the paper and carried out experiment. The material is removed from the workpiece by fixed abrasives and scratching the surface to be finished in grinding process. In order to increase machining accuracy and efficiency, it is necessary to analyze the machining parameters of grinding process. The emphasis is the effect of machining parameters on roughness of surface and mass loss of workpiece by a set of experiments in this paper.

Abstract: Thermal errors and force-induced errors are two most significant sources of the NC grinding machine inaccuracy. And error compensation technique is an effective way to improve the manufacturing accuracy of the NC machine tools. Effective compensation relies on an accurate error model that can predict the errors exactly during machining. In this paper, a PSO–BP neural network modeling technique has been developed to build the model of the dynamic and highly nonlinear thermal errors and grinding force induced errors. The PSO–BP neural network modeling technique not only enhances the prediction accuracy of the model but also reduces the training time of the neural networks. The radial error of a grinding machine has been reduced from 27 to 8μmafter compensating its thermal error and force-induced error in this paper.

Abstract: The cutting-direction burr is one of the important factors that influence the edge quality and performance of precision parts. The cutting-direction burr formation process is simulated with DeformTH3D. The mechanism of cutting-direction burr formation is analyzed in terms of the results of the simulation. The negative shear zone and initiation negative shear angle are discussed too. Study results show that the deformation of
CDE is an important factor affect the cutting direction burrs’ size and shape.

Abstract: A new non-destructive method was developed to identify the grinding mode of silicon wafers, which is based on the information of subsurface cracks extracted from the surface topography of the ground silicon wafers measured with a 3D surface profiler. We examined extensive measurement data of the surface topography of silicon wafers processed by single grain grinding or real grinding operation, and our results show that the information about median cracks could be captured if the lateral sampling interval of the 3D surface profiler is small enough, even if the grain depth of cut is below 20nm. If the maximum valley of the measured surface topography is approximately equal to the grain depth of cut, surface formation will be under ductile mode, whereas, if the maximum valley is several times larger than the grain depth of cut, surface formation will be under brittle mode. According to this criterion, silicon wafers ground by ductile mode or brittle mode could be identified rapidly and conveniently. Experimental validation shows that this method is accurate.

Abstract: The fundamental experiment of the grinding of the stainless steel using the metal bonded CBN wheel which was excellent in wear resistance was conducted. The most appropriate grinding conditions were obtained by clarifying wear process of grinding wheel and finished ground surface quality. When grinding was carried out up to stock removal 7000mm3/mm, radial wear of grinding wheel %R is 3μm and surface roughness Rz was 0.5μm or less. The grinding ratio Gr becomes about 3000, and long life grinding with little change of surface roughness was possible.

Abstract: In profile envelope process of form cutter for involute gear, the grinding depth is variable which causes grinding force to change on a large scale and the profile error of envelope to increase. To improve form cutter accuracy, a closed-loop control system was designed to accomplish control of envelope process. For complicated dynamic process, fuzzy controller is used to adjust parameters online. By measuring grinding force, characteristic information of grinding process is acquired. Regulation factor of feed rate is determined by grinding force ratio, force deviation and its change rate used as evaluation indexes. Thus, fuzzy control of constant force grinding process is accomplished. Simulation and cutter grinding test indicates that the system has high precision and stability, and reduces cutter error effectively.

Abstract: The fluid magnetic abrasives (FMA) are a new type of precision finishing abrasives, which can be used to finish the parts with intricate or complex shape to a quite low surface roughness value. As a key parameter, the magnetic saturation flux density has a great impact on the design of finishing devices and the control of finishing process. In order to measure the magnetic flux density and determine the magnetization curve of FMA, a new apparatus has been developed. The measuring mechanism and the experimental apparatus are presented. The experimental results are discussed as well in this paper.

Abstract: A planet diamond abrasivetool can achieve the purpose of widening grinding area, improving the use efficiency of abrasives and reducing the cost, which doesn’t need any dressing techniques and tools. It could solve some problems of diamond abrasivetool, such as inefficiency of abrasive use, deficiency of cooling, repetitiousness of dressing and so on. This paper describes the characteristics of the planet-abrasivetool and presents an equation for grinding a curving face by the new tool on five-axis grinding machine. At last, the developmental potential of the planet-abrasivetool is predicted.

Abstract: This paper presented a new technology, which was the online wheel wear evaluation in grinding WC-Co ceramic coating by using wavelet packet decomposition. On the basis of the measurement methods, theory of online wear evaluation of wheel was introduced. And the selection principle of characteristic signals was brought forward, the grinding acceleration signal was the best choice among many characteristic signals. The time domain signal analysis method of wavelet packet decomposition was analyzed. Lastly, experiments on the wear of wheel were performed, and the experimental results showed the validity of the method.

Abstract: This paper provides a novel process that can readily make abrasive tools bonded ultraviolet-curing resin. Excellent characteristics of ultraviolet-curing resin make it possible for bonding abrasive tools. Moreover, more applications demonstrate that ultraviolet-curing abrasive tools possess excellent properties without the shortcomings that are encountered in the case of the conventional resin bonded abrasive tools. Furthermore, various factors influencing the qualities of ultraviolet-curing abrasive tools are discussed.