Analysis of Current Areas of Research in Production of Multifunctional Materials for Extreme Operating Conditions

Essential part of strategic objects in oil/gas and machine-building complexes, transport industry and bridge building are operated in the conditions of simultaneous effect of low temperatures, static and dynamic loads as well as intensive wear. High-strength cold-resistance steels are considered as one of the materials, which can be used in such conditions. At present time, providing of principally new qualitative combination of properties of such steels is the actual scientific problem; the main parameters of these steels should be superior to the existing international analogues, they should present the unique combination of high strength, ductility as well as wear and cold resistance at the temperatures down to -70 °C. However, improvement of strength properties and hardness of rolled products leads to substantial decrease of cold resistance and ductility of steel; so, reaching of combination between high strength state and cold resistance is possible during definite structural and phase transformations, occurring in steels. Regularities of phase and structural transformations, occurring in high-strength cold-resistant steel with the following chemical composition (%, mass.): 0.15 C; 1.5 Mn; 0.20 Si; 1.7 (Ni+Cu); 0.035 (Ti+V+Nb); 0.0040 B during continuous cooling, were established in this research. Thermokinetic diagram of decomposition of overcooled austenite was built. It is shown, that steel with above-mentioned composition, which contains mainly if lathe martensite with small amount of bainite, is forming during continuous cooling with rate within the range 10-110 °С/с. Most part of martensite with lathe morphology can provide high strength of the researched steel, presence of dispersed structure of low-carbon bainite can provide high characteristics of resistance to brittle destruction, and hardness more than 350 HBW, which is achieved during cooling with rate more than 50 °С/с can provide high wear resistance.

Section: Introductionmentioning

confidence: 99%

“…In this connection, providing of the principally new combination of properties in high-strength cold-resistance materials, is one of the actual scientific problems. Such combination includes [5,6]:…”

Section: Introductionmentioning

confidence: 99%

Study of phase and structural transformations in overcooled austenite for high-strength cold resistant steel during continuous cooling

Efimova,

Emaleeva,

Gulin

et al. 2023

“…Manufacture of new steels with simultaneous combination of high strength and ductility as well as cold resistance at the temperature -70 °С and increased corrosion resistance in H 2 S-and CO 2 -containing environments is required for operation of pipes and equipment at gas, gas-condensate and oil deposits in the Far North and Arctic regions [1][2][3][4][5][6][7][8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Perspective high-strength pipe steel with increased corrosion cold resistance

Poletskov,

Koptseva,

Kuznetsova

et al. 2023

The scientists of Nosov Magnitogorsk State Technical University developed the new steel with 0.08C-1.50Mn-1.20Cr-0.06Nb-0.04Ti alloying system. Phase transformations of undercooled austenite were examined via dilatometric analysis using Gleeble 3500 complex. Metallographic analysis of the structure, which is forming during continuous cooling, is carried out. Thermokinetic and structural diagrams of steel were built. The conditions of controlled rolling and accelerated cooling of the developed steel are suggested; they provide increased strength (ı т =520-560 N/mm 2 , ı в =600-673 N/mm 2 ; į 5 =26-23.5 %; HBW 207-229), cold resistance down to -70 °С (KCV -70 =252-245 J/cm 2 ; KCU -60 =330-295 J/cm 2 ), as well as increased corrosion resistance in carbon dioxide and hydrogen sulfide environments (HIC, SSC). Providing of such favourable combination of properties makes it possible to use the new steel for manufacture of pipes of different strength classes in oil and gas industry, for operation in the Far North regions.

“…In this case majority of the existing innovations provide production of materials with extremely specialized purposes. In this connection, the unique combinations of requirements for production of new steels, which are characterized by simultaneous high strength and ductility as well as wear resistance, atmospheric resistance and cold resistance at the temperature down to minus 70 °С were developed by the group of scientists from Nosov Magnitogorsk State Technical University [3][4][5]. Such properties determine possibility of simultaneous multirole application of these steels in constructions and objects of Russian oil and gas industry as well as in the areas of bridge construction, building, transport and heavy machinebuilding and other industries.…”

Section: Introductionmentioning

confidence: 99%

Influence of heat treatment on forming the complex of properties for high-strength cold-resistance steel

Полецков¹,

Копцева²,

Efimova³

et al. 2023

Creation of materials for application in the extremal operating conditions, including Arctic and Far North regions, is connected with solving of several problems caused by the effect of static, cyclic and dynamic loads, intensive wear, extra low temperatures etc. A group of scientists from Nosov Magnitogorsk State Technical University has developed the unique combinations of requirements for production of new steels, which are characterized by simultaneous high strength and ductility as well as wear resistance, atmospheric resistance and cold resistance at the temperature down to minus 70 °С. Such properties determine possibility of multirole application of these steels in constructions and objects of Russian oil and gas industry as well as in the areas of bridge construction, building, transport and heavy machine-building and other industries. Production of such steels with different alloying systems, i.e. Si-Mn-Мo and Si-Mn-Ni-Mo with microalloying is mastering at Magnitogorsk Iron and Steel Works in cooperation with Nosov Magnitogorsk State Technical University, within the framework of solving the problem of foreign import replacement. In this case the range of requirements for different concrete grades of multi-functional materials is varied within rather wide range: ı в -from 580 to 1500 MPa, ı 0,2 -from 500 to 1100 MPa, į 5 -from 10 to 20 %, KСV -70 -from 25 to 100 J/cm 2 . Influence of heat treatment procedures (quenching with consequent tempering) on forming the complex of mechanical properties and low-temperature impact strength for highstrength low carbon steels with Si-Mn-Мo and Si-Mn-Ni-Mo alloying systems is examined in this research.