Jan W. Pilarczyk

Effect of hydrodynamic and roller die drawing on the texture of high carbon steel wires

Abstract The effect of hydrodynamic and roller die drawing on the ferrite texture of high carbon steel wires with diameter 3.8 and 3.0 mm has been investigated. Pole figures, inverse pole figures and orientation distribution functions were determined for final and intermediate wire diameters. The average fibre texture 〈110〉 is the most homogeneous in hydrodynamically drawn wires when compared to conventionally drawn wires and to wires drawn through roller dies. At an increase of the total reduction from 54.3% to 71.5%, the increase of the 〈110〉 fibre texture was observed for wires which were drawn hydrodynamically and conventionally. Wires drawn in a roller die revealed a decrease of the 〈110〉 fibre texture with an increase of total reduction.

Effect of Roller Die Drawing on Structure, Texture and Other Properties of High Carbon Steel Wires

In the work the effect of application of roller dies in process of drawing of high carbon steel wires for their structure, texture, residual stresses, surface roughness and mechanical properties has been investigated. Among structural features alignment of cementite lamellae to the wire axis by means of SEM and Pericolor 1500 has been quantitatively determined. Degree of cementite lamellae fracture in colonies parallel to wire axis has been estimated by Langford method. Obtained results were compared with those structural features for conventionally and hydrodynamically drawn wires. It has been found that degree of alignment of cementite lamellae in wires drawn in roller dies was smaller than in wires drawn conventionally and hydrodynamically but in the case of fracture degree the opposite result was noticed. Residual stresses were determined by electrochemical reversal pickling in water solution of sulphuric acid. A significant drop of longitudinal residual stresses in surface layer of wires drawn in roller die has been observed as compared to those stresses for conventionally and hydrodynamically drawn wires. Surface roughness of wires was measured with FORM TALYSURF profilographometer. It has been proved thad roller die drawing has formed very smooth surface with much smaller longitudinal and circumferential roghness parameters that for surface of wires drawn conventionally and hydrodynamically. In the work the tensile, yield and fatigue strength of tested wires were determined. It has been concluded that roller die drawing has many advantages as compared to conventional process and should be implemented in wire industry for larger scale.

Analysis of Textures of Wires Drawn in Pressure and Roller Dies with ODF

In the work orientation distribution functions (ODF) were determined for wires drawn in pressure and roller dies from a high carbon steel wire rod with a diameter 5.5 mm to wires with a diameter 3.8 mm and 3.0 mm. For a comparison ODFs for wires drawn conventionally were also determined. The texture was measured on the cross sections of investigated wires prepared in a form of squares to eliminate the effect of the surface layer. In the first stage of a drawing with a total reduction of 54.3% it has been found that in wires drawn conventionally (KI), in pressure dies (HI) and in roller dies (RI) a strong <110> fibre-texture exist with a value of the ODF equal to about 3.2 for all tested wires. At an increase of the total reduction from 54.3% to 71.5% values of ODF were different for different methods of drawing. For wires with a diameter 3.0 mm drawn conventionally (KF) it was equal 4.25 and for wires drawn in pressure dies (HF) the ODF value was the highest and equal to 4.4. For wires drawn in roller dies the ODF value was the lowest and equal only to 2.6. It means that in spite of the increase of the total reduction roller die drawing results in a decrease of the sharpness of the fibre texture <110>. In conventional drawing and in pressure dies drawing an increase of the <110> texture has been noticed with the increase of the total reduction. In addition to a strong <110> texture component, specimens K and H also featured weak <311> and <310> components. In R specimens there were more of such additional components after the first stage of drawing i.e. <311>, <310>, <210>, <211> and after the second stage of drawing (total area reduction 71.5%) - <311>, <310>.