Results from turning experiments and finite element analysis (FEA) addressing workpiece distortion are presented in this paper. The influence of workpiece clamping, cutting speed, depth of cut and feed on roundness of 100Cr6 (SAE 52 100) rings was analyzed. Induced residual stresses were released by stress relief annealing and the resulting roundnesses of rings were correlated to the cutting parameters. Additionally surface residual stresses for selected rings were measured and correlated to the clamping technique. The influence of clamping on workpiece deformation was also examined by means of FEA. Measured clamping forces were taken as input parameters for the calculations. Coordinate measurements show a major influence of the clamping technique on workpiece deformation. Surface residual stresses correlate with radial workpiece deformation and reach maximum values in the tensile domain at positions of clamping jaws. Results from turning experiments show that with rising cutting speeds the value for the roundness inclines slightly. For higher depths of cut a decreasing tendency for the roundness can be observed although process forces increase. Finally turning with higher feeds leads to even higher process forces and hence, to higher roundness values. In general stress relief annealing shifts the roundnesses of machined rings to higher values.
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