Stainless steel wire, also known as stainless steel strand, mainly comes in two forms: spring wire and screw wire. During the use of stainless steel wire, the phenomenon of wire breaking during drawing is common. The main reasons for this include poor surface quality of the wire, with defects such as scars and indentations on the surface after rolling, which can form crack sources during the drawing process. These cracks propagate from the edge towards the center, resulting in a diagonal fracture. To prevent such issues from occurring when using stainless steel wire, the following measures can be taken, as shared by the editor of Yongda Group, a specialist in stainless steel products.
First, Surface Quality: Factors affecting the surface quality of the wire include billet quality and rolling processes. Defects in the billet, such as slag inclusion, scabs, and microcracks, can be addressed by controlling the secondary cooling water during casting. As for rolling, issues like iron oxide scale pressing, folding, and scratching can be prevented through enhanced inspection and process control.
Second, Optimization of Post-furnace Refining Processes: Inclusions in the wire, such as Al2O3, SiO2, and CaO-based brittle composite inclusions, can be improved by reducing the free oxygen content in the molten steel and controlling the slag basicity during post-furnace refining. This improves the size, shape, and plasticity of the inclusions, enhancing the purity of the steel. Increasing the argon blowing time and flow rate enables larger inclusion particles to float to the surface more effectively. Plasticizing treatment of the inclusions transforms high-melting-point brittle inclusions into low-melting-point ones, facilitating deformation during cold working.
Third, Reducing Steel Superheat and Controlling Centerline Shrinkage, Porosity, and Segregation in Billets: By controlling the pouring temperature of the steel, the billet temperature, and the drawing speed, combined with the use of mold electromagnetic stirring and soft reduction techniques, the carbon segregation and inclusion clustering in high-carbon steel can be improved, thereby reducing the occurrence of brittle fractures caused by carbon segregation.
