Effect of thermomechanical processing of building stainless wire to increase its durability

Abstract

A traditional use of high cumulative reduction ratios is not effective for manufacturing wire with high performance and mechanical properties, since cold plastic deformation reduces the wire diameter, while hot deformation has its own limitations. Thus, thermomechanical treatment of rolled steel has a huge potential to reduce costs and improve product quality when used in the construction industry. Such processing allows metalworking industries to increase the economic effect due to a more complete satisfaction of the requirements for the mechanical properties of finished rolled products. The article developed a new technology for thermomechanical processing of stainless steel wire, consisting of preliminary heat treatment to obtain an austenitic structure and traditional drawing followed by cryogenic cooling. As a result of such treatment, an ultrafine-grained structure was obtained, consisting of a mixture of austenite and α-martensite, with high strength and plastic properties. To analyze the features of the obtained microstructures, modern methods of metallographic analysis were used, such as scanning electron microscopy, transmission electron microscopy, and analysis of backscattered electron diffraction patterns. The microstructure is obtained after deformation at both temperatures and consists of a mixture of α-martensite and austenite. A structure with an average grain size of 0.5 µm was obtained by drawing using cryogenic cooling, and a microstructure of 1 µm was obtained at room temperature. The results obtained allow us to expect an increase in the performance and durability of stainless steel wire, which can be used for various purposes.