Fabrication of ultra-high strength and low carbon steel wire with continuously fibrous crystals

The new fabrication methods of reinforcing ultra-high strength and low carbon steel wires with continuously fibrous crystals are presented in this paper. Q235 steel casting billet was obtained by the continuously unidirectional solidification method. In the process of the continuous casting the shape of the solid-liquid interface and processing parameters were controlled to obtain continuously unidirectional columnar crystals in the cast steel. The processing parameters were as follows: the smelting temperature was 1560degrees C, the volume of spraying water was 2000L/h, the pulling velocity was 0.2mm/s, the distance between the freezer outlet and the top of the water-cooling zone was 20mm and the cast billet was Phi 10mm in diameter. Then in the case of room temperature the cast billet was directly drawn from Phi 10mm to Phi 3mm in diameter. The obtained fibrous microstructure of steel wire was observed. Mechanical properties of steel wires were: sigma(b) >1000MPa, delta=8-10%.