Abstract
Residual stresses in affected layers due to turning, planing, milling, belt grinding and surface grinding were studied experimentally. These affected layers are called uni-directional machined layers. Residual strain distributions in the layer depend on machining direction and these phenomena are generated by residual shear phase stresses. In the layers, the stresses are generated by cutting and burnishing actions of machining. Thermal actions do not generate the shear stresses but negate ones. In this report, it is mainly shown that residual shear phase stresses depend on machining methods and machining conditions. In affected layers due to cutting, there exist strong preferred orientations or fiber textures. In ground layers, however, fiber textures are weak. On the other hand, it can be considered that the microscopic shear stresses are mainly generated by slip in principal slip plane of α-iron crystals. Therefore, it becomes evident that the shear stresses in affected layer due to cutting are larger than ones in ground layers. A method of calculation was shown which determined stress components using three strain components of sin2ψ diagrams obtained by X-ray strain measurement. Namely, the shear stress due to cutting is larger than the one due to grinding. In affected layers due to grinding and cutting, it is also found that the maximum shear stress exists below the surface.
