Advanced Materials Research Vols. 126-128

Abstract: Using the cross-section angle polishing microscopy, the subsurface damage of the silicon wafers (100) ground by the diamond wheels with different grain size were investigated, and subsurface damage distributions in different crystal orientations and radial locations of the silicon wafers (100) were analyzed. The experiment results showed that the grain size of diamond wheel has great influence on the subsurface damage depth of the ground wafer. On the ground wafer without spark-out process, the subsurface damage depth increased along the radical direction from the centre to the edge and the subsurface damage depth in <110> crystal orientation was larger than that in <100> crystal orientation; but on the ground wafer with spark-out process, the subsurface damage depth in different crystal orientations and radial locations become uniform.

Abstract: Computer simulation is an important method to research the grinding mechanism and optimize the grinding process parameters. Especially in recent years as the development of computer calculation speed, the improvement of computer graphics theory and the gradual maturity of artificial intelligence technology, experts and scholars whose research subject related grinding had done a lot of work on grinding simulation. This paper describes the main contents grinding of the grinding simulation research work made in recent years. Include some of the key research results of the present grinding simulation, the major difficulties in grinding simulation and the research trends are summarized in this paper.

Abstract: Spherical silicon balls are applied to photovoltaic energy conversion. Silicon balls are produced by droplet spray method as well as abrasive machining of a single crystalline silicon wafer. A reflective mirror is used to maximize the solar cell efficiency. It is demonstrated the solar cell efficiency depends on the crystalline structure of silicon balls and the mirror in the module.

Abstract: In order to solve the problem that selecting process parameters is difficult and inefficient in NC camshaft grinding, a case-based process expert system is presented, which takes frame method to present cases and utilizes case-based reasoning as the core mechanism of system. One of the typical cases of NC camshaft grinding which are stored in the case base of expert system is composed of three parts including description, solution and evaluation. The expert system generates a new case description according to the characteristics of camshaft to be processed, then forms an evaluation parameter from the similarity and the confidence. In the end, process intelligent matching is obtained by applying the system.

Abstract: Coated abrasives are extensively used for manual operations such us cleaning, deburring, polishing, etc. With the trend towards increased production rates, demands on coated abrasive belts are becoming increasingly severe. . Experimental investigations are to be made to know the effects of the process parameters on the performance of the surface belt grinding process. It is necessary to investigate the effect of flexing along with other input process parameters on output. In the present work the Taguchi’s experimental design method is used for performing the belt grinding process on the stainless steel AISI 304 and optimizing the process parameters. Thus, this research aims at right choice of flexing and grinding parameters for the coated abrasive belts. The results were further analysed by Taguchi’s signal to noise ratio for finding the optimum process parameters.

Abstract: The effects of ultrasonic frequency on the grinding force and surface quality were analyzed from the grinding experiment on ZTA nano-composite ceramics. The results indicate that, in the same parameters, ultrasonic normal grinding force is about 65 to 85 percents of the ordinary grinding condition, and the surface quality is better than that of ordinary grinding condition, as the frequency increasing, this trend will be more evident. The reasons for it were also discussed from microscopic and the nonlocal theory in this paper.

Abstract: Based on good processing property of two-dimentional ultrasonic vibration assisted grinding (TUVAG), the precision finishing of nano-zirconia toughened alumina ceramics (nano-ZTA) is carried out. According to theoretical analysis, TUVAG may obtain higher machining efficiency and better surface quality. Especially, experimental results show it may obtain the compressive stress in the finished surface of nano-ZTA that may restrain the expansion of surface microcrack, and surface residual stress of nano-ZTA under TUVAG differs from that under diamond grinding, and TUVAG may obtain the better surface quality of nano-ZTA than diamond grinding, as is characterized by scanning electronic microscope (SEM). As a result, it is good for TUVAG as a kind of processing method for nano-ZTA.

Abstract: Abrasive flow machining (AFM) has become one of the more attractive finishing processes used in applications such as deburring, recast layer removal, radiusing as well as for polishing. Recently, there has been renewed interest in developing low cost/ low pressure modular AFM systems and media. The media which contains the abrasive particles is the key element in ensuring efficient material removal and a good surface finish. In this paper, the authors will present their work on the development and characterization of a new abrasive media formulation.

Abstract: This paper focuses on experimental investigation on high speed grinding of 40 Cr steel with vitrified CBN grinding wheel, the effect of grinding process parameters, such as grinding speed, depth of cut, and feed rate, on the grinding force and surface roughness are analyzed The experimental results reveal that the grinding force decreases with higher grinding speed and increases with the addition of depth of cut or feed rate, and the surface roughness is satisfactory in high speed grinding.

Abstract: To reduce costs in the manufacturing and usage of grinding wheels, we investigate several methods of adjusting the sharpness of grinding wheels that involve heat treatment and irradiation by ultraviolet (UV) light. We confirm that heat treatment in a furnace of phenol-resin grinding wheels for aluminium leads to improved grinding ability of the wheels for stainless steel and also prevents swarf loading. Next, we clarify that treating the surface of grinding wheels by UV irradiation and heat blowing has a similar effect as heat treatment in a furnace. These treatments reduce the force ratio in surface grinding. Although UV irradiation and heat-blowing affect only the surface layer, heat treatment in a furnace affects the entire wheel. Therefore, thickness of the affected layer varies as a function of the UV-irradiation time. Finally, we applied this technique to other resin-bond wheels and found that the same effect is obtained for polyester-bond grinding wheels. However, heat treatment does not improve the grinding ability of epoxy-bond wheels with high heat resistance. In this case, UV irradiation proved to be an effective method.