This study investigates the grinding of sintered silicon nitride using a SiC wheel with a fine abrasive grit size and dense vitreous bond. The difference of hardness between the green SiC abrasive and sintered Si3N4 workpiece (25.5 vs. 13.7 GPa) is small. Large grinding forces, particularly the specific tangential grinding forces, are observed in SiC grinding of Si3N4. The measured specific gri...

Introduction When the grinding wheel specifications are properly chosen, a SiC grinding wheel performs remarkably well for grinding partially stabilized MgO-ZrO2 ceramics (MgO-PSZ). Rather surprisingly, the highest Gratios are obtained at higher grinding rates for the SiC wheel. This, and the fact that SiC grinding wheels can be readily shaped for use in precision cylindrical form grinding, has...

Surface roughness is a significant parameter which determines the efficiency of optical components. Surface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. It is meaningful to rapid evaluate the surface roughness through the measurement of different grinding parameters. In this study, a cup diamond wheel (D64) is used in grinding pr...

This research is to investigate the dynamic characteristics of the grinding process. A kind of robust grinding wheel reciprocating arrangement is schemed out, which realizes the precise point-grinding machining. The grinding wheel reciprocating movement is driven by a linear motor to replace the traditional crank or hydraulic pressure drive device. Based on the time series method, the modal exp...

Grinding is a key physical element in America’s Cup sailing. This study aimed to describe kinematics and muscle activation patterns in relation to torque applied in forward and backward grinding. Ten male America’s Cup sailors (33.6 ̆ 5.7 years, 97.9 ̆ 13.4 kg, 186.6 ̆ 7.4 cm) completed forward and backward grinding on a customised grinding ergometer. In forward grinding peak torque (77 Nm) occ...

Abstract This study here by presents a method for comparative assessment of grinding wheels during the grinding process of hard-to-cut materials. The method in question consists of carrying out a short grinding cut in plunge grinding kinematics using grinding wheels with a customized macro-geometry upon the active surface. The work presents examples of this method’s efficacy when applied to the...

A mathematical description of grinding processes used in powder technologies is developed. A grinding equation, an operator equation, connecting the final particle size distribution function to the particle size distribution function before the grinding process is studied. The mathematical model introduced here can be used to predict the results of grinding, to construct grinding systems with d...

This paper investigates experimentally the effect of compressed cold air (CCA) and vegetable oil on the surface integrity and residual tresses of ground tool steel components. It shows that CCA can reduce grinding temperature and produce a compressive residual stress up o the grinding depth of 30 m. CCA can also improve surface finish while keeping grinding forces low. Oil was found to be more ...

this study investigates the influence of some chemical additives such as methanol, ethanol, sodium oleat, chloroform and sodium hexametaphosphate (shmp) on the dry fine grinding of calcite (x50= 33 µm) using a stirred media mill. the experiments were carried out by a batch operation, and the change in colour properties (ry, whiteness and yellowness) of calcite powder. the results showed that th...

copper smelting slags are hard materials. therefore,to recover their copper by flotation method, grinding should be carried out to obtain optimal particle size. copper smelting slags in the bardeskan district, with work index of 16.24 kwh/st, were grinded for 65 minutes to reach an acceptable degree of freedom for the flotation tests, with particle size of 80%, smaller than 70 μm. with this gri...