The results of grinding are highly dependent on conditions of workpiece removal process. The material is removed by an unspecified number of abrasive grains of irregular shape and random distribution on the grinding wheel active surface. The interaction between the abrasive grain and the workpiece can be divided into three stages: (i) rubbing, (ii) ploughing and (iii) chip formation. Reciprocal contribution of each stage is dependent on the properties of the workpiece, the grinding parameters, the friction condition between the abrasive grain and the workpiece and the shape of the grains. In the article, the results of numerical and experimental process in the analysis of grinding of Ti-6Al-4V titanium alloy, using a conventional grinding wheel and a newly developed grinding wheel with aggregates of grains, were presented. The analysis of influence of the geometric parameters of the abrasive aggregates and the abrasive grains on the effectiveness of the workpiece removal process is presented. The effects of the geometrical parameters of grains and abrasive aggregates in direction of motion as well as in transversal direction on the size of ridges were determined. It has been observed that increase of the length of sideway material displacement results in the decrease of ridge formation. The results of a numerical analysis were confirmed by experimental research. The analysis of the impact of utilization of abrasive aggregates on the grinding forces, grinding-specific energy and surface roughness was performed. The impact of abrasive aggregates on the decrease of grinding forces and specific energy and the increase of quality of ground surface was observed.

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The shape of the cutting blades of the abrasive grains has an influence on the material separation process in the machining zone. The paper analyzes the influence of the geometrical parameters of the abrasive grains (rake angle γ, apex angle ε, opening angle α), as well as width bz and length bb of the cutting zone on the material removal efficiency. The material removal efficiency was determined taking into account the volume of the removed material VG and the volume of lateral piles-up VR. The analyses were carried out on the basis of the results of experimental and simulations using the finite element method. The relationship between the selected geometric parameters characterizing the cutting zone and the coefficient characterizing the efficiency of the material removal process was determined. A strong influence of the opening angle α as well as the width bz and length bb of the cutting zone on the material removal process by abrasive grain was demonstrated. It was observed that the wide cutting edge, and thus the large opening angle α of the grain, reduced the size of the pile-ups and more effectively removed the chip material.

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In this article, the methodology of using probabilistic models of the grinding tool wear process is presented. Probabilistic modeling with empirical data allowed determining the values of other important process features. Among them, the distribution of active grains lifetime or distribution of cumulative attritious wear of the grinding grain apex could be distinguished. The results of modeling and wear analysis of grinding wheels as well as experimental results on peripheral grinding with zoned grinding wheels are presented. The analyzed grinding wheels consisted of three layers: two identical external layers with conventional structure and one internal layer containing the addition of abrasive aggregates. The external layers were profiled by chamfering the edges. As a result, their nominal surfaces were conical. The internal layer had a cylindrical shape and was designed for smoothing the surface after machining with external part. The tools were designed to increase the grinding efficiency and hence a good quality of machined surfaces could be acquired. For the experimental tests, the Ti6Al4V titanium alloy was used. It was found that the change in the shape and position of the grinding zone, as a result of volumetric wheel wear, caused a significant change in fracturing intensity. In the case of multilayer grinding tools, the wear process depends on the physical properties of each layer and their participation during machining of the workpiece. The presented methodology could be applied to a study on the machining process stages, which concerns temporary states and their variability according to the machining time.This makes it possible to reduce the cost of developing new tools dedicated to specific applications.