Abstract
In this work the influence of the drawing speed on lubrication conditions and mechanical properties of high carbon steel wires drawn in conventional and hydrodynamic dies has been assessed. The drawing process of ϕ5.5 mm wires to the final wire of ϕ1.7 mm was conducted in 12 passes, in industrial conditions, by means of a modern Koch multi-die drawing machine. The drawing speeds in the last passes were: 5, 10, 15, 20 and 25 m/s. For final wires ϕ1.7 mm the investigation of mechanical properties has been carried out, in which yield strength, tensile strength, uniform and total elongation and also number of twists were determined. It has been shown that the increase of drawing speed from 5 m/s up to 25 m/s caused the increase by 6% strength properties and decrease of plasticity properties by 10%. Higher values of tensile strength and yield strength of the wires drawn conventionally with high speeds are associated with worse conditions, while in case of wires drawn hydrodynamically the main factor which caused the increase of strength properties was high lubricant pressure in hydrodynamic die, which caused the increase of total draft.
Effect of Pass Schedule on the Microstructures and Mechanical Properties of Multi-step Cold Rolled High Carbon Steel Wires
