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The influence of impurities on the solid-solution hardening of cold-rolled low-carbon steel components is considered, by calculation and experiment. To confirm the results, data regarding the influence of the chemical composition on the properties of cold-rolled 08Ю steel components (produced by Cherepovets Metallurgical Works, OAO Severstal’) are subjected to statistical analysis, with the formulation of a regression model. The factors that underlie the influence of impurities on the properties of 08Ю steel are investigated, and the optimal impurity contents for products of the highest extrusion category are established.

Recommendations have been developed on optimizing hot rolling in the finishing train of a 2000 mill and subsequent coiling of the rolled product. The goal was to improve the stampability characteristics of steel 08Yu. Specific recommendations were also made on the optimum annealing and temper-rolling regimes to improve the mechanical characteristics of steel 08Yu. The results of studies show that the structure and properties of the cold-rolled product are significantly affected by the conditions of precipitation of different particles of nonmetallic inclusions. It is shown that it would be expedient to analyze the thermodynamics and kinetics of these processes and study the morphology of the particles and the state of the solid solution. Recommendations on chemical composition and process parameters that were developed on the basis of the results of such analysis are now making it possible to consistently obtain steel 08Yu with high properties.

Results are presented from a study of dual phase ferritic-martensitic steels (DFMS) of two compositions: 0.08% C, 1.18% Si, 1.81% Mn, and 0.39% Cr; 0.07% C, 1.16% Si, 1.79% Mn, 0.40% Cr, and 0.14% V. In order to obtain different structural parameters in the two DFMS, heat treatments were given to 3.2-mm-thick specimens of steel sheet with different initial structures: the ferrite-pearlite-bainite mixture obtained directly from hot rolling; a ferrite matrix with spheroidized carbides, obtained by heating the hot-rolled sheet and holding it at 1050°C for 1 h, cooling the sheet with the furnace to 690°C, holding the sheet at this temperature for 15 h, and then further cooling the sheet together with the furnace. The results confirmed the positive effect of “new” ferrite on the ductility of DFMS. This effect is connected not with the intrinsic properties of new ferrite but with the factors that help increase the initial volume of this component in the steel (the amount of new ferrite in the investigated steels ranges up to 20–25%).

One of the main trends in the development of materials for the body and other parts of automobiles is the greater use of high-strength steels, this being done in order to make the vehicle safer and lighter. The need for this change stems from the continual tightening of standards on tailpipe emissions. The largest metallurgical companies that presently make automobile sheet have been working with the main Russian automobile manufacturers to develop steels with improved commercial properties. This article presents results from studies conducted to optimize the technology used to make rolled products of high-strength, ultralow-carbon steels 01YuTB an 01YuPTB for the automotive industry. The optimized technology includes heat treatment in a continuous annealing furnace. Emphasis should be given to developing technical recommendations on how to optimally combine strength, stampability, and a guaranteed level of the BH-effect (BH2 ≥ 30–40 N/mm2) in the production of automobile sheet of strength class K180, as well as BH steels of strength class K220 or higher.

Results obtained from comprehensive corrosion tests have established that in addition to limiting the content of corrosion-active nonmetallic inclusions in steel to make it resistant to corrosion, it is also desirable to restrict the steel's contents of sulfur, manganese, and silicon. The new specifications for steels 20-KS (corrosion-resistant) and 20-KSKh (corrosion- and cold-resistant) were therefore developed based on steel 20sp, which is distinguished by its relatively low contents of manganese and silicon. These steels also have a limited sulfur content, and they are microalloyed with niobium or vanadium to obtain a fine-grained structure. All the other indices of the steels meet the requirements of SNiP. Mastering the production of welded tubes made of steel 20-KSKh is an important step toward the goal of improving the durability of oil-field tubing in Western Siberia. Such tubes are the first type of tubular metal product that has been guaranteed to be clean with respect to corrosion-active nonmetallic inclusions, and guarantees of this kind are a prerequisite to ensuring that pipelines have satisfactory corrosion resistance and last for their normal service life.