Measurement of Residual Stress in High-speed Machined Surfaces Using Machining Center

摘要

The effects of cutting speed, table speed and cutting depth are investigated on the residual stress of the surfaces, which are machined by a machining center, by the measurements using a three-dimensional X-ray diffraction and the texture. It is found that the pole figures of the surfaces machined by the machining center are different from those by shaping machines and horizontal milling machines. The texture of cut surface by the shaping machines and horizontal milling machines is the rolling texture, on the other hand the texture of cut surface by the machining center is weak a texture similar to that of the initial stages due to rolling contact fatigue. In cutting by the machining center, the residual stress increases as the cutting speed increases and it decreases as the table speed and cutting depth increase because of the influence of the chips. It is found that the residual stress occurred by the machining center is half that of the horizontal milling machines under the optimal cutting condition. Based on the results obtained from the measurement of texture and three-dimensional stress analysis, it can be concluded that machining with shaping machines and horizontal milling machines shows strong machining as the feature, while high-speed heavy machining with a machining center indicates easygoing processing from the viewpoint of the crystal deformation behavior, neglecting the damage of tools.