Effect of Boron on the Microstructure and Mechanical Properties of Low-Carbon Tube Steel

2019 ◽  
Vol 946 ◽  
pp. 374-379 ◽  
Author(s):  
Anatoly A. Babenko ◽  
Vladimir I. Zhuchkov ◽  
Natalia I. Selmenskih
Keyword(s):  
Mechanical Properties ◽  
Nonmetallic Inclusions ◽  
Pipe Steel ◽  
Steel Sample ◽  
Tube Steel ◽  
Low Carbon ◽  
Rolled Metal ◽  
Carbon Tube ◽  
Additional Thermal Treatment ◽  
Average Size

Effects of boron in low-carbon tube steel grade 17G1SU on nonmetallic inclusions, structure and mechanical properties were investigated. Experimental samples of rolled metal containing boron 0.006 and 0.011% are characterized by predominantly small, nonmetallic inclusions not more than 5 μm, which are represented by complex alumomagnesium spinels in the shell of manganese and calcium sulfides, and small silicate inclusions. Nonmetallic inclusions of comparative pipe steel sample, containing no boron characterized by the presence of larger inclusions presented complex oxysulfide and sulfide films. The main structural component of the comparative and experimental samples is ferrite. The introduction of boron is contributed by a decrease in the average size of ferritic grains from 8.7 μm (0% B) to 6.2 (0.006% B). Increasing the boron content to 0.011% leads to slight increase (up to 6.8 microns) of the size. The mechanical properties of 10 μm rolled metal pipe steel ensured the production of rolled products of strength class X80 without additional (thermal) treatment, as a result of the reduction in the size and shape of nonmetallic inclusions, and formation of dispersed structure.

Effect of cooling rate on the structure and properties of low-carbon tube steel

Metallurgist ◽  
2008 ◽  
Vol 52 (7-8) ◽  
pp. 464-469 ◽  
Author(s):  
I. Yu. Pyshmintsev ◽  
A. N. Boryakova ◽  
M. A. Smirnov
Keyword(s):  
Cooling Rate ◽  
Tube Steel ◽  
Structure And Properties ◽  
Low Carbon ◽  
Carbon Tube

The assessment of the level of local strengthening of pipe steel welded connections

2020 ◽  
Vol 10 (3) ◽  
pp. 252-262
Author(s):  
Marat Z. Yamilev ◽  
◽  
Egor А. Tigulev ◽  
Andrey А. Raspopov ◽  
◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Numerical Model ◽  
Bearing Capacity ◽  
Pipe Steel ◽  
Carbon Steels ◽  
Strengthening Effect ◽  
Low Carbon ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Welded Connection

The metal welding is accompanied by the formation of mechanically non-homogenous sections of welded connection. The pipeline welded connections also have sections, which are different in structure, chemical composition and mechanical properties. The mechanical inhomogeneity affects the load bearing capacity of welded connection and the structure as a whole, which is necessary to take into consideration when performing calculation analysis. So far, the specialists have established the dependencies in assessment of welded connection strength with various types of heterogeneous sections. However, this phenomenon has received little attention in case of pipeline welded connections made of low carbon steels. The existing theoretical models do not reflect actual anisotropy of mechanical properties of the welded connections and weld adjacent zone. The present study considers the model of welded connections of K56 pipe steels with various strength characteristics of sections of welded seam and weld adjacent zone, without defects. The assessment of mechanical inhomogeneity influence on load bearing capacity of welded connections was performed by applying the finite-element modelling of its stress-strain state. The developed numerical model helps to determine and optimize the criteria of testing of full scale samples of pipe steel welded connections with regards to the implementation of local strengthening effect. The research results demonstrated that the degree of contact strengthening in welded connections with X-shape grooving is higher than in welded connections with V-shaped grooving by 8 % at similar relative thickness of soft interlayer. The suggested numerical model can be applied for detailed calculations of pipelines with regards to the mechanical inhomogeneity of its welded connections.

The Evolution of Structure and Mechanical Properties of Fe-Mn-V-Ti-0,1C Low-Carbon Steel Subjected to Severe Plastic Deformation and Subsequent Annealing

2012 ◽  
Vol 715-716 ◽  
pp. 994-999 ◽  
Author(s):  
Galina G. Zakharova ◽  
Elena G. Astafurova ◽  
Evgeny V. Naydenkin ◽  
Georgy I. Raab ◽  
Sergey V. Dobatkin
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
High Pressure Torsion ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Angular Pressing ◽  
Ultrafine Grained ◽  
Average Size

The present work deals with the evolution of mechanical properties and structure of low-carbon Fe-1,12Mn-0,08V-0,07Ti-0,1C (wt.%) steel after severe plastic deformation (SPD) and high-temperature annealing. Steel in initial ferritic-pearlitic state was deformed by equal channel angular pressing (ECAP) at T=200°C and high pressure torsion (HPT) at room temperature. The evolution of ultrafine grained structure and its thermal stability were investigated after annealing at 400-700°C for 1 hour. The results shown that SPD leads to formation of structure with an average size of (sub-) grain of 260 nm after ECAP and 90 nm after HPT. Ultrafine grained structures produced by SPD reveal a high thermal stability up to 500°C after ECAP and 400°C after HPT. At higher annealing temperatures a growth of structural elements and a decrease in microhardness were observed.

scholarly journals The study of the microstructure and mechanical properties of low carbon steel, microalloying by boron

2019 ◽  
Vol 57 (1) ◽  
pp. 143-148
Author(s):  
Anatoly A. Babenko ◽  
◽  
Natalia I. Selmensky ◽  
Alena G. Upolovnikova ◽  
◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Steel ◽  
Nonmetallic Inclusions ◽  
Volume Fraction ◽  
Low Carbon Steel ◽  
Strength Properties ◽  
Rolled Steel ◽  
Low Carbon ◽  
Bainite Structure ◽  
Temporary Resistance

The paper presents the results of the study of non-metallic inclusions, the structure and mechanical properties of low carbon steel, microalloying by boron. The study of the amount and composition of nonmetallic inclusions showed that with the introduction of boron the volume fraction of oxide and oxysulfide inclusions increases and the volume fraction of sulfide inclusions significantly decreases. At the same time, the alloying of steel with boron increases to 99.7% the proportion of inclusions with a size of no more than 5 microns against 80.6% in the metal without boron. In the metal with boron, nonmetallic inclusions larger than 10 μm are absent, while in the metal without boron their share is 13.6%. Studies have shown that in a metal containing 0.011% boron, independent boron-containing inclusions were not detected. Boron was not detected in the composition of the studied nonmetallic inclusions. In all samples, steel nonmetallic inclusions are represented mainly by oxide, oxysulfide and sulfide inclusions. In the boron-free steel, a small amount of perlite is present along with the ferritic phase. Steel microalloying by boron is accompanied by the formation of a dispersed ferrite-bainite structure, which consists of fine-grained ferrite with bainite sites with a tendency to form bainite strips along the rolling direction. The microhardness of ferrite and perlite in steel without boron does not exceed an average of 180 and 214 HV10, respectively. It is noted that the presence of boron in steel in an amount of 0.011% increases the microhardness of ferrite to 260 HV10 and bainite to 335 HV10. The mechanical properties of hot-rolled steel with a thickness of 10 mm from boron-containing low-alloyed steel, due to the predominant formation of small rounded inclusions with a size of no more than 5 microns and the formation of a fine ferrite-bainite structure, are characterized by enhanced strength properties with preservation of plastic characteristics. The absolute values of the yield strength and temporary resistance of steel with boron reach 575 and 650 MPa, respectively. With such strength properties of metal, high plastic characteristics are preserved. Rolled steel without boron is characterized by reduced to 540 and 610 MPa tensile strength and temporary resistance, respectively.

scholarly journals The effect of warm rolling on structure and mechanical properties of low carbon pipe steel

2015 ◽  
Vol 5 (1) ◽  
pp. 48-51 ◽  
Author(s):  
S. N. Sergeev ◽  
I. M. Safarov ◽  
A. V. Korznikov ◽  
R. M. Galeyev ◽  
S. V. Gladkovsky ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Pipe Steel ◽  
Warm Rolling ◽  
Low Carbon

The Effect of Boron, Manganese and Sulfur on the Microstructure and Mechanical Properties of Pipe Steel 17G1SU

2021 ◽  
Vol 316 ◽  
pp. 408-412
Author(s):  
Anatoly A. Babenko ◽  
Leonid A. Smirnov ◽  
Alena G. Upolovnikova
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Boron Concentration ◽  
Pipe Steel ◽  
Manganese Content ◽  
Steel Sample ◽  
Fine Grained ◽  
Microstructure And Mechanical Properties ◽  
Fine Grained Structure ◽  
Bainitic Structure

The paper presents the results of the effect of boron, manganese and sulfur on the microstructure and mechanical properties of pipe steel 17G1SU. It was shown that the microstructure of boron-free steel sample containing 1.4% Mn and 0.01% S consists mainly of ferrite and a small amount of perlite. Samples microalloyed by boron are represented by a dispersed ferritic-bainitic structure. A decrease in ferrite grain size from 8.7 μm, in a comparative sample without boron containing 1.4% Mn and 0.010% S to 5.8 μm in a sample of steel containing 0.006% B, 1.6% Mn and 0.011% S, shows increasing the dispersity of the ferritic-bainitic structure. A decrease in the manganese content to 1.4, sulfur to 0.004% and an increase in boron concentration to 0.0011%, despite an increase in grain size to 6.8 μm, retain a fine-grained structure. The effect of boron, manganese, and sulfur content on the microhardness of the structural phases of the studied pipe steel samples is noted. The smallest microhardness of ferrite and perlite is observed in the base sample without boron, reaching 180 and 214 HV10, respectively. The microalloying of pipe steel containing 1.6% Mn, 0.011% S with boron is accompanied by an increase in the microhardness of the bainitic phase to 314 HV10, which increases to 400 HV10 with an increase in boron concentration to 0.011%, and a decrease in the content of manganese and sulfur to 1.4 and 0.003%. In this case, the microhardness of the ferrite phase, reaching an increase to 260 HV10, is practically independent of the content of boron, manganese, and sulfur. The mechanical properties of the experimental metal rolling with a thickness of 10 mm provide the production of rolled steel of strength class X80, without heat treatment, regardless of the content of boron, manganese, and sulfur, as a result of the formation of a finely dispersed ferrite-bainitic structure.

scholarly journals Effect of scrap using in charge on the microstructure and properties of ZhS6U nickel-based superalloy. Part 2. Structure analysis and mechanical properties of ZhS6U prepared with scrap

2019 ◽  
Vol 62 (7) ◽  
pp. 525-530
Author(s):  
A. V. Koltygin ◽  
V. E. Bazhenov ◽  
A. I. Bazlov ◽  
T. A. Bazlova ◽  
V. D. Belov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Cross Sections ◽  
Nonmetallic Inclusions ◽  
Vacuum Arc ◽  
Nickel Base Superalloy ◽  
Nickel Based Superalloy ◽  
Vacuum Arc Furnace ◽  
Nickel Base ◽  
Average Size

The second part of the article considers influence of the scrap amount on structure and mechanical properties of ZhS6U-VI nickelbased superalloy. As the use of scrap is associated with the possibility of alloy contamination by nonmetallic inclusions and loss of alloying elements, the influence of scrap on alloy structure and mechanical properties is in great importance. The samples with diameter of 12  mm were melted in a vacuum arc furnace and were casted into a copper mold from the virgin ZhS6U-VI alloy without scrap and from alloys with 50  % and 100  % of scrap. The alloys structures were investigated using optical microscopy on etched metallographic sections that were cut from the samples’ cross-sections. The studies were carried out on the as-cast samples and the samples after solution heat treatment for 4  hours at 1210  °C. The slightly higher nonmetallic inclusions content were observed in the structure of the alloy melted with scrap in comparison with virgin alloy melted without scrap. For the sample that was melted from 100  % of scrap the inclusions secure level is 3 (ASTM E 45-97) with an average size of inclusions of 28.4  ±  0.2  μm. Herewith the presence of single large inclusions with a size of not more than 70  microns was noted. However, it has no effect on the alloy mechanical properties. Mechanical properties after heat treatment (ultimate strength (UTS)  =  1090  –  1100  МPа and elongation (El)  =  9  –  11  %) were obtained on the samples melted using 50 and 100  % of scrap and fully correspond to the TU1-92-177-91 standard for ZhS6U-VI nickel-base superalloy. During solidification most of the large nonmetallic inclusions are concentrated under casting surface, which makes their machining difficult. Because of that the use of 100  % scrap without its preliminary processing is not recommended. Acceptable results were achieved when the 50  % of scrap was used. 

The Evolution of Structure and Mechanical Properties of Fe-Mn-V-Ti-0,1C Low-Carbon Steel Subjected to Severe Plastic Deformation and Subsequent Annealing

2010 ◽  
Vol 667-669 ◽  
pp. 325-330 ◽  
Author(s):  
Galina G. Zakharova ◽  
Elena G. Astafurova ◽  
Evgeny V. Naydenkin ◽  
Georgy I. Raab ◽  
Sergey V. Dobatkin
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
High Pressure Torsion ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Angular Pressing ◽  
Ultrafine Grained ◽  
Average Size

The present work deals with the evolution of mechanical properties and structure of low-carbon Fe-1,12Mn-0,08V-0,07Ti-0,1C (wt.%) steel after severe plastic deformation (SPD) and high-temperature annealing. Steel in initial ferritic-pearlitic state was deformed by equal channel angular pressing (ECAP) at T=200°C and high pressure torsion (HPT) at room temperature. The evolution of ultrafine grained structure and its thermal stability were investigated after annealing at 400-700°C for 1 hour. The results shown that SPD leads to formation of structure with an average size of (sub-) grain of 260 nm after ECAP and 90 nm after HPT. Ultrafine grained structures produced by SPD reveal a high thermal stability up to 500°C after ECAP and 400°C after HPT. At higher annealing temperatures a growth of structural elements and a decrease in microhardness were observed.

scholarly journals Structure and properties of 17G1S-U low-carbon pipe steel microalloyed by boron

2018 ◽  
Vol 61 (10) ◽  
pp. 774-779
Author(s):  
A. A. Babenko ◽  
V. I. Zhuchkov ◽  
N. I. Sel’menskikh ◽  
A. G. Upolovnikova
Keyword(s):  
Strength Class ◽  
Nonmetallic Inclusions ◽  
Pipe Steel ◽  
Metal Structure ◽  
Strength Properties ◽  
Structure And Properties ◽  
Low Carbon ◽  
Preferential Formation ◽  
Bainitic Structure ◽  
Temporary Resistance

The results of analysis of the influence of boron microalloying on structure and properties of 17G1S-U pipe steel are given in the paper. Studies of metal structure were performed by electron microscopy and local X-ray spectral analysis. It has been established that metal containing 0.006 % of boron is characterized by an increased volume concentration to 0.029 % of oxide (OS) and oxysulfide (OSB) inclusions, whose content in metal without boron reaches 0.006 %. Separate sulphide inclusions (CB), whose concentration does not exceed 0.004 % against 0.029 % in a metal without boron, containing 0.01 % S is practically absent in the metal with boron containing 0.003 % S. The microalloying of pipe steel by boron has ensured the preferential formation of small nonmetallic inclusions, evenly distributed in the volume of metal. The proportion of nonmetallic inclusions with size less than 2 (rm is 76.1 %, whereas in steel without boron it is only 58.5 %. In this case, large nonmetallic inclusions of more than 10 rm are practically absent in the sample with boron. Their share does not exceed 0.6 %, which is 22 times less than their amount in the sample without boron. The structure of the sample without boron consists mainly of ferrite and a small amount of perlite, and the sample with boron is represented by a dispersed ferritic-bainitic structure. Increasing the microhardness of both ferrite and pearlite 80 and 100 HV10, respectively, is observed by adding boron to steel. The mechanical properties of 10 mm hot rolled metal from boron-containing 17G1S-U pipe steel are characterized by increased strength properties with preservation of plastic characteristics, due to the formation of predominantly small nonmetallic inclusions and a finely dispersed ferritic-bainitic structure. The absolute values of the yield stress and the time resistance of pipe steel containing in mass %: 0.006 B and 0.003 S are achieved without heat treatment at 585 and 685 MPa, respectively, and meet the X80 strength class, while retaining sufficiently high plastic characteristics. The pipe steel without boron containing 0.01 % of S belongs to the X70 strength class and is characterized by tensile strength lowered to 540 and 610 MPa and a temporary resistance, respectively.

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