Investigation of texture and residual stresses of pearlite carbon steel wire after combined plastic deformation

Method of combined deformational processing of carbon steel wire is presented in the paper. The essence of the method consists in applying on the continuously moving wire the deformation of tension and compression at drawing, bending and torsion kinds of deformation when passing the four-rolls system. Advantages of the method consist in using tools of metal ware manufacturing and simplicity of the equipment. The scheme of the laboratory setup which makes it possible to apply on the wire different kinds of plastic deformation (tension, compression, alternate bending, torsion) is presented. Pearlite carbon steel wire with 0.5 %C was chosen as an object for investigation as the in-demand metal product. Modes of the carbon steel wire combined deformational processing are presented. The effect of deformational processing on texture, mechanical properties and residual stresses in carbon steel wire with 0.5% C was found studied experimentally. Texture and residual stresses were investigated by X-ray analysis using Кα - radiation of chromium anode of SHIMADZU XRD-7000 diffractometer. The accuracy of residual stresses and texture measurement during X-ray analysis was improved by special sample preparation when pieces of the carbon steel wire after deformational processing were tightly pressed in the special polymer. The axial texture was investigated by diffractometer I(α) curves. Residual stresses were estimated along the (211) line of α-phase (double diffraction angle 2θ ≈ 156°). It was shown that crystallographic texture after all kinds of deformational processing by drawing, alternate bending and torsion and their combination became doublecomponent: + . This promotes the increase of carbon steel wire strength and ductile properties after combined deformational processing and proves the high importance of texture in ensuring the mechanical properties level. The obtained experimental results showed that the method of combined deformational processing by drawing with alternate bending and torsion has significant advantage as compared with industrial technology of carbon steel wire manufacturing due to possibility to improve its mechanical properties in a wide range.