Contribuição para o processo de retificação plana de superfícies interrompidas

Abstract

Grinding is a machining process by abrasion, in which material removal occurs through abrasive grits with non-defined geometry that have poor thermal conductivity, which, combined with the low material removal rate, generates a large amount of heat that is transferred to workpiece during grinding. Depending on the case, this heat can cause thermal damages such as burning, microstructural changes, cracks, among others) and thereby compromise the functionality of the component. In this sense, a situation that is not yet fully known in the literature is how thermal damage behaves in parts with interrupted surfaces. In this sense, the present work aims to contribute generation of data to peripheral surface grinding of a ABNT 316 UF stainless steel samples with number of channels using an aluminum oxide grinding wheel under different cutting conditions. Samples with 4 and 6 channels were tested (that comprises an interrupted surface) and 3 different radial depth of cut values (15 µm, 30 µm and 45 µm). As output variables, the roughness parameters (Ra, Rz, Rt and Rq), microhardness, grinding power and texture and quality of the ground surfaces (through Scanning Electron Microscopy) images were studied. In general, the results showed that the use of lower radial depth of cut values resulted in lower roughness values and surfaces with better texture. The influence of channels on the microhardness was practically negligible. In terms of number of grooves, the smaller the number of grooves, the lower surface roughness and improved surface texture.