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The paper presents a brief analytical review of the current state of research in the field of recovery and its modeling in order to predict the structure and properties, as well as a review of experimental research methods and mathematical models of the processes of structure formation during annealing of cold-rolled steels. The paper also presents the results of an experimental study of the recovery process in cold-rolled automotive steels using various techniques and describes a mathematical model for calculating the kinetics of this process depending on the temperature and chemical composition of steels. [ABSTRACT FROM AUTHOR]

Strain aging of pipe steels 06G2FB and 07G2MFB with ferrite-pearlite and ferrite-bainite structures is investigated. It is established that a ferrite-bainite structure is more inclined towards strain aging than a ferrite-pearlite structure. The tendency towards strain aging of steel with a ferrite-bainite structure increases with increasing austenitizing temperature. During hot plastic deformation there is development of recrystallization and the tendency towards strain aging decreases. [ABSTRACT FROM AUTHOR]

The effect of cooling regime after rolling and also subsequent spheroidizing annealing are studied for rolled product of special alloy steel 40Kh of an industrial melt on metal structural state and amount of relative reduction of area. It is established that the amount of reduction of area, varying uniformly round rolled product capacity for cold upsetting, increases with a reduction in the proportion of ferrite and an increase in steel ferrite-pearlite structure uniformity and fineness. The most favorable microstructure and high value for reduction of area occur after spheroidizing annealing of rolled product with a bainitic structure. [ABSTRACT FROM AUTHOR]

Relations predicting the mechanical properties of bars of austenitic stainless steels are already available, but no systematic work has been performed to predict the strength of cold rolled and annealed stainless steels. The tensile properties of a large number of cold rolled and annealed AISI 304 stainless steel are here correlated with their chemical composition and microstructure. Quantitative effects of various strengthening mechanisms such as grain size, δ-ferrite content and solid solution strengthening by both interstitial and substitutional solutes are described. Interstitial solutes have by far the greatest strengthening effect and, among the substitutional solutes, the ferrite-stabilizing elements have a greater effect than the austenitestabilizing elements. Regression equations are developed that predict with good accuracy the proof stress and tensile strength in AISI 304 stainless steels. [ABSTRACT FROM AUTHOR]

Traditionally high strength (σ ≥ 400 N/mm) rolled sheet thicker than 50-60 mm of low-carbon structural steel is produced by hot rolling technology followed by normalizing or hardening and tempering. Contemporary equipment makes it possible to produce rolled product 50-140 mm thick of low carbon steel by thermomechanical rolling and to obtain a required set of properties without expenditure on production operations connected with additional metal heating such as normalizing and tempering. Results are given in this article for studying one of the thick sheet property indices, i.e., structure nonuniformity through plate thickness. The microstructure is compared for rolled sheet 100 mm thick of low-carbon microalloyed steel structural steel produced in the 4200 NLMK Dansteel mill by thermomechanical rolling technology (TMT) with the microstructure obtained as a result of hot rolling followed by normalizing (HT). Grain sizes are determined at different points of rolled product layer thickness, and histograms are plotted for their distribution, making it possible to compare the degree of inhomogeneity for the microstructure with respect to grain size. The type, size, and density of carbonitride particles are determined at distances of 1/2 and 1/4 through the thickness of 100 mm plate after TMT and HT. [ABSTRACT FROM AUTHOR]

Steel microalloying combinations are studied, and heat treatment regimes are determined for preparing the required level of mechanical properties providing high quality characteristics for steels used in the manufacture of casings of strength group K55 according to the API standard Spec 5CT, including cold resistance to −60°C. [ABSTRACT FROM AUTHOR]

Results are given for a study of the effect of heat treatment parameters on supercooled austenite transformation kinetics in steel 20GFL. Specimen microstructure is studied in specimens 10 × 10 mm in cross section with the following regimes: soaking at 860 and 940°C, cooling in an air stream 3-8 m/sec through a channel 100 mm in diameter. The change in microstructure features in the course of high-temperature soaking at 940°C for 30 and 60 min after specimen cooling in salt water is determined. It is established that in cast steel there is chemical composition microliquation inhomogeneity with respect to carbon and manganese, which decreases during soaking (60 min) and is accompanied by austenite grain growth. Critical cooling rates are determined with which a structure forms containing upper and lower bainite. A dependence is obtained for impact strength KCV on soaking temperature and time in the γ-region. The effect is demonstrated of alloying with vanadium on the possibility of stimulating the formation of globular lower bainite components. [ABSTRACT FROM AUTHOR]

The nature of corrosion process development is studied by observing surface condition with potentiometric polarization. It is established that an increase in martensite content within steel structure increases the intensity of corrosion process development considerably. The high sensitivity of the corrosion test method developed to steel structural state (structural component content), and also prospects for using it instead of tests in accordance with GOST 9.911−89 are demonstrated. [ABSTRACT FROM AUTHOR]

The effect of accelerated cooling parameters on microstructure and hydrogen initiated cracking (HIC) is studied for thick-walled low-alloy steels of strength categories X52-X65 used for manufacturing large diameter pipes intended for operation in hydrogen sulfide media. Optimum accelerated cooling regimes are determined providing formation of a ferrite-bainite microstructure throughout the rolled product's thickness, exhibiting improved hydrogen cracking resistance. [ABSTRACT FROM AUTHOR]

On the basis of studying the effect of chemical composition, controlled rolling temperature and deformation parameters, and accelerated cooling parameters, technology is developed for manufacturing pipe steel of strength class K60, providing under Ural Steel mill 2800 conditions the required level of mechanical properties and cold resistance. [ABSTRACT FROM AUTHOR]

The effect of temperature regimes for accelerated cooling in the range 820-590°C on low-carbon microalloyed steel plate microstructure and properties is studied. Microstructure formation features are determined with unequal cooling conditions over a workpiece length during manufacture by controlled rolling technology with accelerated cooling. Recommendations are made for improving property uniformity over the length during industrial production. [ABSTRACT FROM AUTHOR]

The effect of deformation temperature scheme in the finish rolling stage and cooling regime on structural component morphology and set of strength properties for pipe steel is demonstrated. Improved chemical composition and production regimes are established on the basis of quantitative correlations for structure and properties of pipe steel using a Gleeble simulation system. Results are presented for manufacture of industrial test batches of rolled sheet of strength classes K65-K70 (X80-X90). [ABSTRACT FROM AUTHOR]

A comprehensive study is provided for the effect of a ferrite-pearlite microstructure with a pearlite content from 0 to 100% on the main operating properties of structural steel, including fracture toughness and ductility, brittle failure resistance, and crack resistance. It is found that an increase in carbon content is accompanied by rapid ferrite grain refinement. It is confirmed that an increase in pearlite content in a microstructure, especially above 20% has a marked, but not always favorable effect on all steel deformation and failure characteristics. [ABSTRACT FROM AUTHOR]

Reaction of cast iron base with iron oxide FeO at 1173-1373 K is studied. It is shown that oxidation of cast iron base carbon promotes transformation of ferrite into austenite, and with rapid cooling this is converted into martensite. The hardness of ferritic-pearlitic cast iron after quenching is commensurate with that of malleable cast iron. [ABSTRACT FROM AUTHOR]

The effect of low-alloy steel structure on strength and ductility properties, including the amount of relative elongation, is studied. The effect of phase composition, ratio, and dispersion of structural components on mechanical properties in tension is analyzed. [ABSTRACT FROM AUTHOR]

The expediency of classifying the microstructure of low-carbon pipe steels is demonstrated. The main structures that should be considered in its development are investigated. [ABSTRACT FROM AUTHOR]

This article examines the main features of the stages in the production of steel skelp on the 2800 mill at Ural Steel before and after its reconstruction. It is shown that there are significant differences in the mechanical properties and microstructure of rolled products made by controlled rolling versus a technology that follows controlled rolling with accelerated cooling. [ABSTRACT FROM AUTHOR]

We studied structure formation in high-strength strip for trunk pipelines made from steel in strength classes Kh80–Kh100. The structural morphology was shown to have an effect on the mechanical properties of the thick rolled sheet. Weldability studies and low-temperature brittle-fracture-resistance studies were performed on the steels developed as part of this study. [ABSTRACT FROM AUTHOR]

The desired set of characteristics can be obtained in tube steels with a ferritic-bainitic structure by varying their chemical composition, monitoring the parameters of the thermomechanical rolling operation, and properly choosing the parameters for accelerated cooling of the rolled products. [ABSTRACT FROM AUTHOR]