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In this study, an additive manufacturing process based on digital light processing was employed for a quick, flexible, and economical fabrication of resin bonded SiC grinding tools. The grinding wheel has been fabricated using laboratory manufacturing processes that utilize ultraviolet-curable resins and conventional abrasives. Also, desirable geometries and features like integrated coolant holes, which are difficult or even almost impossible to manufacture by conventional processes, are easily achievable. Grinding experiments were carried out by different process parameters, and with two different grinding wheels, i.e., with and without cooling channels with different concentrations (25 wt.% and 50 wt.% grains) to evaluate the grinding efficiency of the produced tools. Grinding forces, tool wear, tool loading, and ground surface quality were measured and analyzed. The wear rates of the grinding wheels with cooling channels were generally less than those without cooling channels, particularly in the deep grinding processes with large contact areas. Grinding tests on a hardened steel have shown that the integration of cooling lubricant channels almost prevents the wheel loading. In addition, by increasing the cutting speed (from 15 to 30 m/s) and decreasing the feed rate (from 10 to 2 m/min), the grinding wheel wear was significantly reduced. Furthermore, surface grinding of aluminum resulted in surface roughness values (Ra) in the range of 1 μm to 2.5 μm, while a Ra of about 0.2 μm was achieved by grinding hardened steel (100Cr6) with the same grinding conditions. Using the higher SiC-grain concentration (50 wt.%), it was determined that the surface roughness was 50% finer. Additionally the tool wear was significantly reduced (up to 30 times depending on the process parameters). The wear characteristics of the grinding wheel were analyzed through a novel image processing system. Significant correlations were found between the wear flat of grains and the increase in grinding forces due to the tool wear.

Simulation and grinding experiments on soda-lime glass were performed in this paper. The influence of grinding parameters on the grinding force, surface roughness, and morphology of soda-lime glass after processing was studied in this paper. The change in grinding force, processed surface morphology, and surface roughness after grinding of different coated micro-grinding tools was discussed. Simulation results and experimental results have the same trend. The conclusion shows that as the grinding speed increases, the grinding depth and feed speed decrease, the grinding force decreases, the machined surface roughness value decreases, the surface morphology is smoother, and the surface quality is better. Under different cooling conditions, the machined surface roughness value of wet grinding is lower, and the surface quality is better. The surface quality of diamond-coated micro-grinding tools is better, by comparing CBN-coated micro-grinding tools and diamond-coated micro-grinding tools of the same particle size, and it is more suitable for grinding hard and brittleness materials such as glass. The research results provide a theoretical reference and experimental basis for reducing the grinding force of coated micro-grinding tools and improving the quality and processing performance of the machined surface.

Abstract The CVD diamond micro-grinding tool highly promising for micro-scale high accuracy machining. To improve the lubrication and chip removal performance in the grinding zone, a kind of micro-structured CVD diamond micro-grinding tool. Firstly, the commercial FEM software was adopted to analyze the effects of micro-structure parameters on the deformation and stress distribution of the micro-grinding tool. And then, the coolant flow fields in the grinding zone included the macro flow field, micro flow field and chip evacuation were simulated. The effects of micro-structure parameters and grinding parameters on the flow field performance and the transport capacity of chips were obtained, which provides a basis for the surface micro-structure design and optimization of the CVD diamond micro-grinding tools.

Because of the random distribution of diamond abrasive grains on the surface and the obstruction of chip flow during processing, conventional grinding tool cannot meet the requirements of the machining precision. Therefore, the emergency of special grinding tools such as surface structured grinding wheels improves the machining precision. In this study, rhombus textured grinding tools with different arrangement angles α are manufactured, the grinding mechanism of them is studied, the penetration depth model and grinding force model are established, and the grinding performance of conventional grinding tool and rhombus textured grinding tools are compared. It can be found that when α = 50°, the surface quality of the rhombus textured grinding tools for grinding single crystal silicon and BK7 is significantly better than that of conventional grinding tool, and the surface roughness of single crystal silicon machined by rhombus textured grinding tool is 20.2–37.4% smaller than that of conventional grinding tool. The instantaneous grinding forces of the two kinds of tools are compared, they both conform to the sinusoidal change, but the amplitude of the instantaneous grinding force of conventional grinding tool is at least 22.1% bigger than that of the rhombus textured grinding tool with α = 50°. Furthermore, the average grinding force of the rhombus textured grinding tool with α = 50° is not only very stable, but also much smaller than that of conventional grinding tool. Finally, in order to verify the average grinding force model, the test value of the average grinding force of the rhombus textured grinding tool with α = 50° and the predicted value of the model are compared, when the cutting depth is 20 μm and the material is single-crystal silicon, the average error in the x direction and y direction are 15.2% and 19.0%, respectively.

The monitoring of tool wear plays an important role in improving the processing efficiency and reducing the production cost of enterprises. This paper is focused on the detection of electroplated diamond mill-grinding tools by using the acoustic emission sensor. The wear stages of mill-grinding tools are divided into three parts, namely initial wear stage, normal wear stage, and severe wear stage. The characteristic parameter method and the waveform analysis method are applied to analyze the acoustic emission signals. The wear characteristics of the tool and workpiece in different wear stages are observed and analyzed. The results indicate that the acoustic emission waveform is relatively stable in the initial wear stage, and the continuous acoustic emission signal is dominated. Moreover, the diamond abrasive grains are mainly worn and slightly broken in the normal wear stage, and there are some pits on the machined workpiece surface after the initial wear stage. In the severe wear stage, most of the abrasive grains are broken or broken in a large area, and there are burst acoustic emission signals in the waveform.

Non-productive auxiliary processes affect the single part and small badge production of milling tools. The key production process grinding is inevitably linked to the auxiliary conditioning process. The time demand of those process steps decreases the overall productivity of the manufacturing process. However, today the machine operator decides on conditioning cycles individually by the use of experience. Until today, there is no objective data based approach available that supports the initiation of these conditioning processes or the adaption of the grinding process itself in order to improve its process efficiency. For this purpose, a process-related topography evaluation method of the grinding wheel surface is developed within this study. For the measurement, an optical method based on laser triangulation is used. The measurement system is implemented into a common tool grinding machine tool. In addition, characteristic topography values are defined that show the wear conditions of the grinding tool. Moreover, the data is summarized in a database of wear conditions. The developed measurement method can save grinding and dressing tool resources, process times and minimizes scrap parts. In addition, an adaptation of the process and a targeted launch of auxiliary processes can be enabled. The novel characteristic-based topography measurement creates the opportunity to enhance the tool life of the grinding wheels up to 30% without losing productivity.

The wafer backside grinding process has been a crucial technology to realize multi-layer stacking and chip performance improvement in the three dimension integrated circuits (3D IC) manufacturing. The total thickness variation (TTV) control is the bottleneck in the advanced process. However, the quantitative analysis theory model and adjustment strategy for TTV control are not currently available. This paper developed a comprehensive simulation model based on the optimized grinding tool configuration, and several typical TTV shapes were obtained. The relationship between the TTV feature components and the spindle posture was established. The linear superposition effect of TTV feature components and a new formation mechanism of TTV shape were revealed. It illustrated that the couple variation between the two TTV feature components could not be eliminated completely. To achieve the desired wafer thickness uniformity through a concise spindle posture adjustment operation, an effective strategy for TTV control was proposed. The experiments on TTV optimization were carried out, through which the developed model and TTV control strategy were verified to play a significant role in wafer thickness uniformity improvement. This work revealed a new insight into the fine control method to the TTV optimization, and provided a guidance for high-end grinding tool and advanced thinning process development.

This paper proposes a strategy to overcome the problem of poor surface quality when grinding difficult-to-cut materials at a small scale, by creating a small-scale grinding tool with a regular array structure (SSGT-RAS) through the method of combining low-speed wire electrical discharge turning (LS-WEDT) machine technology and electroplating process. A numerical model is established to describe the surface topography of SSGT-RAS grinding of titanium alloy Ti-6Al-4V, taking into account the shape, size and distribution of the abrasive grains, the plastic material removal mechanism and the machining parameters. The study comparatively analyses the surface morphology characteristics and surface generation mechanism of SSGT-RAS and ordinary cylindrical grinding tool (OCGT) when grinding titanium alloy Ti-6Al-4V with different helical groove depths through side dry grinding experiments. The experimental results show that SSGT-RAS improves the surface quality of the workpiece compared to OCGT, and surface roughness Ra can be reduced by up to 25.20 ~ 27.81% and 21.49 ~ 35.44% at most by changing the feeding velocity and cutting depth, respectively. In addition, increasing helical groove depth further improves the surface quality. A comparative analysis of the simulation and experimental results shows that the prediction error of the surface roughness Ra is within 15.92%. This research expands the preparation process of surface-structured grinding tool at small scale, which has significant theoretical and engineering applications.

In this paper, two different types of discontinuous micro-grinding tools are designed and fabricated, which respectively are straight-type effective units (STR) tool and screw-type effective units (SC) tool, and the number of effective grinding zones is designed as three and four respectively. The grinding mechanism between the workpiece and the abrasive grains of discontinuous micro-grinding tools is studied. Grinding force model of two different types of discontinuous micro-grinding tools is established. In order to verify the correctness of the grinding force model and the superiority of the designed discontinuous micro-grinding tools, a series of contrast experiments between the designed discontinuous micro-grinding tools and regular cylindrical (RC) micro-grinding tool are designed. It is experimentally and then theoretically validated that grinding forces of discontinuous micro-grinding tools are much lower than RC grinding tool. Besides, the grinding force amplitude and the grinding force fluctuation degree of RC tool are greater than that of the four kinds of discontinuous micro-grinding tools. Besides, because the discontinuous micro-grinding tools have good ability of chip removal and chip capacity, the machined surface quality of the four-SC micro-grinding tools is better than that of the RC grinding tool with the increase of feeding velocity. Meanwhile, the fabricated four different types of discontinuous micro-grinding tools were compared in terms of tool wear, workpiece surface quality, and grinding force. Among them, chip removal ability of the four-SC grinding tool is superior to the other micro-grinding tools; therefore, the four-screw-type effective units grinding tool own a better tool wear-resisting property, a longer tool life.

Micro-grinding is a tool based mechanical micromachining process which is mostly applied to create and finish 3D micro-features on hard and brittle materials such as glass, silicon, alumina, etc. Miniature-sized abrasive tool comes in physical contact with the workpiece and removes the unwanted material with mostly nanometric undeformed chip thickness and hence can achieve ductile mode cutting. Electroplated and metal bonded sintered abrasive tools are the most researched micro-grinding tools in terms of their fabrication techniques evolution, design modification, and processing of different materials. In the last decade, researchers have thoroughly investigated the micro-grinding process mechanics and identified different issues along with controlling strategies to improve the process performance. Through experimental and analytical studies, it was shown that process performance could be improved through proper tool modifications, optimum selection of process parameters, proper lubrication media, and most importantly by the development of dedicated machine tools. This paper describes the micro-grinding process mechanism considering tool-workpiece interaction. Thereafter, a comprehensive review on micro-grinding tool manufacturing technologies, issues and controlling strategies, proper machining parameter selection, modeling techniques, and micro-feature generation in various materials is presented. After critical examination of the state of the art of this process, challenges, and limitations in the process establishment and applications are derived. Future research scopes in different aspects of the said process are suggested so as to multiply the process utility.