Influence of Roll Diameter on Material Deformation and Properties during Wire Flat Rolling

The influence of roll diameter on the strain distribution, shape change, contact pressure, and damage value of a workpiece was investigated during wire flat rolling to control the material properties of the flattened wire. The flattened wires fabricated by the four different rolls were compared using finite element analysis. The strain inhomogeneity of the flat-rolled wire increased with the roll diameter; thus, the macroscopic shear bands were strengthened as the roll diameter increased during wire flat rolling. The contact width and lateral spreading of the flattened wire increased with the roll diameter; therefore, the reduction in area decreased with the roll diameter. The contour of the normal contact pressure on the wire surface exhibited a similar pattern regardless of the roll diameter. The contact pressure showed higher values at the entry, edge, and exit zones in the contact area. The distribution of the damage value varied with the roll diameter. The free surface region tended to have the peak damage value during the process; however, the center region exhibited the maximum damage value with the roll diameter. From the perspective of the damage value, the optimum roll diameter was in existence during wire flat rolling. The underlying cause of the different strain distributions, shape changes, and damage values of the flat-rolled wire was the different contact lengths originating from the different roll diameters during wire flat rolling.

ALUMINUM AS MATERIAL FOR INSTALLING AN ELECTRICAL CABLE

«Rolled wire from aluminum alloys of grades 8176 and 8030», manufactured by continuous casting and rolling, or by the combined method of continuous casting and rolling-pressing, designed for the manufacture of wire for electrical purposes, was developed and adopted for use.

Analysis of elastic rolling stand deformation and interstand tension effects on section faults of hot rolled wire rod and bars

The present work aims at the modelling and simulation of the hot rolling process for wire rod and bars. After the fundamentals of plasticity, which are essential for the understanding of the process characteristics have been described, typical section deviations that can be expected in wire rod and bar mills are calculated with help of a numerical simulation model. The model allows the calculation of section shapes under the influence of elastic rolling stand deformations and interstand tensions. From this computational assessment of section faults, the necessity of inline measurement and process control for wire rod and bar mills is shown. This work is part of the PIREF project which incorporates the development of sensors, control systems and process models in order to control the dimensional accuracy of hot rolled wire rod and bars. The metal forming process model, as described here is used internally as a model for the static and kinematic interactions in the rolling process inside of the control model.

Effect of cross-sectional area reduction rate and alloy composition on the formation of -fiber texture in Ti-Mo-Al-Zr alloy wire

Texture formation in Ti-7Mo-8Al-6Zr cold-groove-rolled alloy wires was investigated and compared to that of Ti-5.5Mo-8Al-6Zr. Irregularly textured <001>-fiber was formed in Ti-5.5Mo-8Al-6Zr. The Ti-7Mo-8Al-6Zr cold-groove-rolled wire mainly composed of the β phase though α″ martensite was induced by cold-groove-rolling in the Ti-5.5Mo-8Al-6Zr alloy. From the TEM observations of the severely deformed cold-rolled sheet, α″ martensite was assumed to be induced during cold-groove-rolling and trace α″ was assumed to be retained after cold-groove-rolling. This texture is common in bcc metals and corresponds to the <010>α″ -fiber which is formed in the Ti-5.5Mo-8Al-6Zr alloy when the lattice correspondence between β and α″ is considered. On the other hand, the <001>-fiber was strongly developed in the cold-groove-rolled wire with a reduced cross sectional area of 98% following solution treatment, while this texture was not observed in the specimen with a 60% reduced cross sectional area. The texture formed in solution-treated Ti-7Mo-8Al-6Zr alloy wire was similar to that of the Ti-5.5Mo-8Al-6Zr alloy, although the dominant phase in the cold-groove-rolled specimen differed.