Influence of Residual Stresses on Dimensional Instability of Cold-Formed Workpieces During Machining
- 1 August 1991
- journal article
- review article
- Published by SAGE Publications in Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture
- Vol. 205 (3) , 207-214
- https://doi.org/10.1243/pime_proc_1991_205_070_02
Abstract
The presence of residual stresses in a cold-formed workpiece is unavoidable due to an inhomogeneous flow of metal during the plastic deformation process. The paper deals with the problem of changes in geometry of such a workpiece after machining or heating. An extruded cup and such a cup subjected to ironing were taken into consideration. First circumferential residual stresses were determined experimentally for those cups. Next longitudinal and circumferential grooves were machined on the outer surfaces of the cups. The state of equilibrium of residual stresses was disturbed during machining and the workpieces reacted by deforming. Changes in diameter were measured by using a Zeiss three-coordinate machine and deviations in the radial direction were determined depending on the length and the number of grooves. It was concluded from the experiments that the diameter tolerances taking those changes into account should be higher than 0.4 per cent of the diameter of the extruded cup and 0.2 per cent of the diameter of the ironed cup. Stress relief annealing carried out after machining grooves increased the deviations of diameter.Keywords
This publication has 2 references indexed in Scilit:
- Residual Stresses in Cold-Formed WorkpiecesCIRP Annals, 1985
- Residual Stresses — Measurement and Causes in Machining ProcessesCIRP Annals, 1982