Metal Flow Law of Variable Diameter Metal Wire During Die Drawing

Abstract

The dieless drawn variable diameter metal wire often causes blockage or leakage during subsequent die drawing. It is still not clear that the metal flow law of variable diameter metal wire in the die drawing process. In order to prepare high precision metal wire, it is necessary to study the metal wire flow law in the die drawing process. Variable diameter TC4 titanium alloy wire with reference diameter of 6 mm and variation degree of 10–30% was selected as the workpiece. Deform finite element software was used to simulate the die drawing process of variable diameter TC4 wire. The simulation experiments were carried out under the condition of drawing speed of 0.5 mm/s and die drawing deformation amounts of 10–30%. The metal flow law of the variable diameter metal wire in the die drawing process was analyzed. The results showed that the metal flow directions of the die exit and die entry were consistent with the drawing direction when the TC4 titanium alloy wire entered the drawing die, initiating plastic deformation. There was an inclined angle between the metal flow direction in the deformation zone and the drawing direction. This inclined angle decreased gradually to 0° from the edge to the core of the wire. With the wire diameter variation increasing from 10 to 20%, the variation range of the metal flow velocity at the die entry increased from 0.04 to 0.19 mm/s, that is the greater the wire diameter fluctuation, the larger of the variation range of the metal flow velocity at the die entry. When the wire diameter variation degree increased to 30%, the wire fractured at the die exit and the metal flow velocity be 0 at the die entry.