Adaptive Approach to Structure And Properties Forming in Niobium Alloyed Pipe Steels

Abstract

The results of research aimed at structure formation in niobium alloyed steels for pipe production by means of dynamic recrystallization control during hot rolling at a wide strip mill are shown. Influence of deformation, time and temperature parameters in the continuous roughing train of a wide strip hot rolling mill, on the microstructure of niobium alloyed steels and the level of their mechanical properties is studied. It is shown that within the temperature range of 1000-1050°С in steels X52-X70 grade beside intensive dynamic recrystallization, one can see secondary recrystallization as well. From the obtained data it is evident that niobium alloyed pipe steels with lower carbon content 0.06-0.08 % C mechanical properties are ensured by hard solution strengthening mechanism of Mn combined with Ni and Cr. Optimal both temperature and rate parameters of hot deformation during rolling are determined. It leads to increasing ductility basically toughness of niobium contained steels for pipes.

Effect of Stress-Strain State during Combined Deformation on Microstructure Evolution of High Carbon Steel Wire

“…The advantage of this method is the possibility to use tools operating at wire manufacturing (drawing dies) and cables manufacturing (preformator) technologies. It opens wide horizons for designing new technologies which can be easily adapted to rapidly changed market conditions [21,22].…”

Design of Pipe Steel Hot Rolling Technological Process Based on System Analysis

“…The need of making use of such steels became obvious due to natural resource development in the polar regions and on the Arctic shelf [13][14][15]. At present time the high quality pipe steel sheet can be obtained by thermomechanical rolling which provides control of heating temperature, temperature and reduction at rolling, and cooling after rolling.…”