INFLUENCE OF DAMAGEABILITY OF LOW-ALLOYED STEEL ON ITS PHYSICAL AND MECHANICAL PROPERTIES

High-strength sheet product of low-alloyed steel, used at manufacturing of heavy-loaded structures, must have, apart from wear resistance, high toughness, good weldability, ability to hot and cold forming, machinability and low cost. Combination of these properties based on forming fine grain austenite structure before the martensitic transformation at definite its thermal treatment modes. Results of study of microstructure, fine structure and mechanical properties of high-strength boron-containing low-alloyed steel after different technological methods of the rolled product manufacturing presented: high-temperature hot rolling and twostages controlled rolling with accelerated cooling followed by thermal treatment – quenching with tempering. Variants of optimal modes of thermal treatment determined, providing combination of high level of impact toughness under negative temperatures, hardness and strength properties of sheet product. The two considered in the article technological variants, comprising treatment of low-alloyed steel with boron (hot rolling and two-stages controlled rolling with accelerated cooling) followed by thermal treatment results in forming fine structure of tempered martensite, which provides high mechanical properties, meeting the made requirements. Depending on the heating temperature before quenching in the range 770–950 °С, the morphology of the actual steel grain is changing from elongated to equiaxed, which is connected with the metal recrystallization process during heating after plastic deformation. The study results obtained allow to optimize the thermal treatment processes of sheet product of low-alloyed boron containing steel for particular conditions of application.

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A novel design to enhance the amount of retained austenite and mechanical properties in low-alloyed steel

Scripta Materialia ◽

10.1016/j.scriptamat.2014.06.014 ◽

2014 ◽

Vol 88 ◽

pp. 21-24 ◽

Cited By ~ 56

Author(s):

Ran Ding ◽

Di Tang ◽

Aimin Zhao

Keyword(s):

Mechanical Properties ◽

Retained Austenite ◽

Alloyed Steel ◽

Low Alloyed Steel ◽

Novel Design

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Electron-Beam Cladding of Boron Carbide on Low-Alloyed Steel at the Air Atmosphere

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.698.369 ◽

2014 ◽

Vol 698 ◽

pp. 369-373 ◽

Cited By ~ 2

Author(s):

Dina S. Krivezhenko ◽

I.S. Laptev ◽

T.A. Zimoglyadova

Keyword(s):

Mechanical Properties ◽

Electron Beam ◽

Boron Carbide ◽

Volume Fraction ◽

Steel Substrate ◽

Alloyed Steel ◽

Heterogeneous Structure ◽

Air Atmosphere ◽

Considerable Impact ◽

Low Alloyed Steel

An investigation of coatings obtained by cladding of boron carbide on a low-alloyed steel substrate by an electron beam injected into the air atmosphere was carried out. It was shown that hardened layers had a heterogeneous structure formed during rapid cooling. It was established that a volume fraction of iron borides in the surface layer had a considerable impact on mechanical properties of the material studied.

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Design and Processing of FGCM Materials for Applications Subjected to Intensive Abrasive Wear

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.750.137 ◽

2017 ◽

Vol 750 ◽

pp. 137-141

Author(s):

Ion Badoi ◽

Dan Mihai Constantinescu ◽

Daniel Vlasceanu

Keyword(s):

Mechanical Properties ◽

High Speed ◽

Physical And Mechanical Properties ◽

Functionally Graded ◽

Cold Extrusion ◽

Technological Parameters ◽

Wear Properties ◽

Graded Materials ◽

Low Alloyed Steel ◽

Sic Reinforcement

The present work shows the design criteria of FGCM, respectively selection criteria of PM (Powder Metallurgy) matrix, and use of reinforcement particles in correlation with the mechanical stresses resulting in moulds and punches used for steel cold extrusion, powder compaction, sheet metal stamping and series production of parts processed with these tools. Therefore, sintered and repressed state are analysed, and the microstructural and mechanical properties of steel powders used for matrices development, grade High Speed Steels (HSS), AISI M2 and AISI M4, and low alloyed steel powders Ancorsteel 2000 and Ancorsteel 4600 V are defined. Also there are analysed the physical and mechanical properties of the reinforcement particles TiC, WC, Al2O3, B4C, SiC, etc. Are presented the manufacturing methods, the technological parameters for development of functionally graded materials in vertical and horizontal plans, compacting to 500-600 MPa,, sintering temperature to 1050 °C for SiC reinforcement and 1100-1150 °C for matrix reinforced with Al2O3 , repressing to 600 MPa/1100 °C of sintered preforms, heat treatment and wear properties of FGCM materials as Ancorsteel 2000 and Ancorsteel 4600 reinforced with Al2O3 and SiC particles

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Effect of cooling rate on the microstructure and mechanical properties of a low-carbon low-alloyed steel

Journal of Materials Science ◽

10.1007/s10853-021-05974-3 ◽

2021 ◽

Author(s):

Hongcai Wang ◽

Lijie Cao ◽

Yujiao Li ◽

Mike Schneider ◽

Eric Detemple ◽

...

Keyword(s):

Mechanical Properties ◽

Volume Fraction ◽

Plate Thickness ◽

Microstructural Characterization ◽

Mechanical Tests ◽

Alloyed Steel ◽

Low Carbon ◽

Cooling Rates ◽

Heavy Plate ◽

Low Alloyed Steel

AbstractHeavy plate steels with bainitic microstructures are widely used in industry due to their good combination of strength and toughness. However, obtaining optimal mechanical properties is often challenging due to the complex bainitic microstructures and multiple phase constitutions caused by different cooling rates through the plate thickness. Here, both conventional and advanced microstructural characterization techniques which bridge the meso- and atomic-scales were applied to investigate how microstructure/mechanical property-relationships of a low-carbon low-alloyed steel are affected by phase transformations during continuous cooling. Mechanical tests show that the yield strength increases monotonically when cooling rates increase up to 90 K/s. The present study shows that this is associated with a decrease in the volume fraction of polygonal ferrite (PF) and a refinement of the substructure of degenerated upper bainite (DUB). The fine DUB substructures feature C-rich retained austenite/martensite-austenite (RA/M-A) constitutes which decorate the elongated micrograin boundaries in ferrite. A further increase in strength is observed when needle-shaped cementite precipitates form during water quenching within elongated micrograins. Pure martensite islands on the elongated micrograin boundaries lead to a decreased ductility. The implications for thick section plate processing are discussed based on the findings of the present work.

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