Papers by Author: Wit Grzesik

Abstract: This paper proposes a novel integrated approach to the prediction of surface generation mechanisms which takes into account both cutting process outputs and distortions of the individual feed marks in comparison to an ideal kinematical model. For this task, the recorded surface roughness profile was decomposed using special algorithms. The mechanisms of real surface generation considered include the plastic side flow and spring back effects, the cutting edge sharpness and its wear, and dynamic interactions between the tool and the workpiece. The computation procedure was verified for different workpiece materials in conjunction with uncoated and coated, sharp and worn, tools.

Abstract: This investigation is devoted to the heat flow problem occurring in dry orthogonal machining of a C45 medium carbon steel performed with uncoated single-point carbide tools. Finite Difference Approach (FDA) is applied to predict the variations of temperature distribution, and both average and maximum temperatures at the tool-chip interface, resulting from differentiating the heat flux configuration, and additionally the changes of thermal resistance along the tool-chip contact length. Moreover, some realistic computing errors due to possible measuring variations of the tool-chip contact length and the density and dimension of heat source on the shear plane were assessed and considered as input data in simulations. Finally, the measured values of temperatures using natural tool-work thermocouples have confirmed that the models proposed predict acceptably the average interface temperatures and estimate their maximum values for carbide tools.