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Abstract The surface morphology and roughness of a workpiece are crucial parameters in grinding processes. Accurate prediction of these parameters is essential for maintaining the workpiece’s surface integrity. However, the randomness of abrasive grain shapes and workpiece surface formation behaviors poses significant challenges, and accuracy in current physical mechanism-based predictive models is needed. To address this problem, by using the random plane method and accounting for the random morphology and distribution of abrasive grains, this paper proposes a novel method to model CBN grinding wheels and predict workpiece surface roughness. First, a kinematic model of a single abrasive grain is developed to accurately capture the three-dimensional morphology of the grinding wheel. Next, by formulating an elastic deformation and formation model of the workpiece surface based on Hertz theory, the variation in grinding arc length at different grinding depths is revealed. Subsequently, a predictive model for the surface morphology of the workpiece ground by a single abrasive grain is devised. This model integrates the normal distribution model of abrasive grain size and the spatial distribution model of abrasive grain positions, to elucidate how the circumferential and axial distribution of abrasive grains influences workpiece surface formation. Lastly, by integrating the dynamic effective abrasive grain model, a predictive model for the surface morphology and roughness of the grinding wheel is established. To examine the impact of changing the grit size of the grinding wheel and grinding depth on workpiece surface roughness, and to validate the accuracy of the model, experiments are conducted. Results indicate that the predicted three-dimensional morphology of the grinding wheel and workpiece surfaces closely matches the actual grinding wheel and ground workpiece surfaces, with surface roughness prediction deviations as small as 2.3%.

Abstract Minimum quantity Lubrication (MQL) is a sustainable lubrication system that is famous in many machining systems. It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes. The MQL system is affirmed to exhibit an excellent machining performance, and it is highly economical. The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability, compared to pure oil-based MQL system. Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids. This work presents an experimental study on the tribological performance of SiO2 nanofluid during grinding of Si3N4 ceramic. The effect different grinding modes and lubrication systems during the grinding operation was also analyzed. Different concentrations of the SiO2 nanofluid was manufactured using canola, corn and sunflower oils. The quantitative evaluation of the grinding process was done based on the amount of grinding forces, specific grinding energy, frictional coefficient, and surface integrity. It was found that the canola oil exhibits optimal lubrication performance compared to corn oil, sunflower oil, and traditional lubrication systems. Additionally, the introduction of ultrasonic vibrations with the SiO2 nanofluid in MQL system was found to reduce the specific grinding energy, normal grinding forces, tangential grinding forces, and surface roughness by 65%, 57%, 65%, and 18% respectively. Finally, regression analysis was used to obtain an optimum parameter combinations. The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.

The microstructure, homogeneity, and tribo-corrosion behavior of microwave-developed Nickel as well as titanium dioxide SS-304 cladding surfaces are the primary emphasis of this research. The study includes assessing the hardness enhancement from Ni and TiO2 particles in the cladding surface. The investigation additionally evaluates cladding surface wear rates, friction coefficients, and resistance to corrosion under tribological conditions. The microstructure, homogeneity, and tribo-corrosion behavior of SS-304 cladding surface with Ni and TiO2 developed by microwave cladding energy were investigated in this study. The microstructure was being examined to validate the uniformly homogeneous dispersion of Ni and TiO2 particles, and XRD was employed to determine cladding surface phases. The hardness of the cladding surface was evaluated, and a pin-on-disk tribometer has assessed the wear behavior. Tribo-corrosion was tested in 3.5-percent NaCl solution. To enhance cladding's efficiency, microwave hybrid heating (MHH) utilising charcoal as a susceptor has been employed. Findings exhibited that the microstructure analysis showed that the cladding surface had a uniform distribution of Ni and TiO2 particles and a compact and homogeneous microstructure. The hardness of the cladding surface was significantly improved by about 37.68% due to the incorporation of Ni and 10% TiO2 particles. The FeNi3, NiSi2, Ni3C, NiC, Ni2Si, FeNi, and TiO2 phases were seen by XRD on the cladding surface. The behavior of the cladding surface under tribological conditions was also evaluated using a pin-on-disk tribometer. The outcomes have exhibited that the Ni and 10% TiO2 cladding surface exhibited decreased wear rates and friction coefficients compared to the uncoated SS-304 substrate. Moreover, the tribo-corrosion behavior of the cladding surface was evaluated in a 3.5% NaCl solution. The wear rate and coefficient of friction of Ni and 10% TiO2 cladding surfaces were measured to be 0.00412 mm3/m and 0.297, respectively. The results indicated that the Ni and TiO2 cladding surface had enhanced corrosion resistance compared to the uncoated SS-304 substrate.