Preparation and microstructure characteristics of low-temperature bainite in surface layer of low carbon gear steel

Rolling contact fatigue (RCF) properties of low-temperature bainitic microstructure in the surface layer of a low-carbon steel, obtained by means of carburization and successive lowtemperature austempering were studied. Comparisons were made with those properties of a martensite steel obtained by quenching and tempering. The results showed that the low-temperature bainitic steel exhibits an excellent RCF resistance and reaches a RCF life more than twice that of the martensite steel, presumably as a consequence of the very thin bainite plates (~80 nm in thickness) and the fine-scale dispersion of austenite between the plates. The apparently increased hardness in the surface layer may partly be the cause of the enhanced RCF resistance.

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NICLOY 5

Alloy Digest ◽

10.31399/asm.ad.sa0096 ◽

1960 ◽

Vol 9 (3) ◽

Keyword(s):

Fracture Toughness ◽

Corrosion Resistance ◽

High Temperature ◽

Low Temperature ◽

Physical Properties ◽

Tensile Properties ◽

Ferritic Steel ◽

Heat Treating ◽

Low Carbon ◽

Temperature Performance

Abstract NICLOY 5 is a low carbon, nickel ferritic steel reecommended for low temperature service. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-96. Producer or source: Babcock & Wilcox Company.

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Factors Influencing Dephosphorization of Low Carbon Steel in Converter

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1047.111 ◽

2021 ◽

Vol 1047 ◽

pp. 111-119

Author(s):

Zhao Liu ◽

Shu Sen Cheng ◽

Liang Wang

Keyword(s):

Carbon Steel ◽

Low Temperature ◽

Slag Composition ◽

Phosphorus Content ◽

Low Carbon Steel ◽

Smelting Process ◽

Low Carbon ◽

Factors Influencing ◽

High Basicity ◽

Metal Yield

A 300-metric ton converter in a steel plant in China was studied. The influence of factors such as slag composition and temperature in the smelting process on the dephosphorization effect was statistically analyzed. The dephosphorization ability of slag increased firstly and then decreased with the increase of temperature, basicity and FeO content. Low-temperature, high-basicity and high-oxidizing slag are thermodynamically beneficial to promote the dephosphorization reaction, but the basicity is higher than 4.0, and the temperature is higher than 1640 °C are not conducive to the slag to obtain better fluidity. At the same time, too high FeO content will increase the activity coefficient of P2O5, thereby increasing its activity, which is not conducive to the progress of the dephosphorization reaction. As the end point content of carbon decreases, the oxygen content increases and the phosphorus content decreases. A very low carbon content is not conducive to metal yield and temperature control.

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Increasing Hardness of Surface Layer of Low-Carbon Steel by Account of Plasma Treatment of Coating Modification

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.316.794 ◽

2021 ◽

Vol 316 ◽

pp. 794-802

Author(s):

Andrey E. Balanovsky ◽

Van Trieu Nguyen

Keyword(s):

Surface Layer ◽

Thermal Treatment ◽

Plasma Treatment ◽

Plasma Heating ◽

High Surface ◽

Surface Hardness ◽

High Hardness ◽

Diffusion Region ◽

Low Carbon ◽

Wide Range

The Purpose of paper is to conduct studies to assess the possibility of increasing the hardness of the surface layer of steel St3 grade by plasma heating of the applied surface coating containing powder alloy PR-N80X13S2R. Mixtures of pasta were divided into 2 groups: for furnace chemical-thermal treatment and plasma surface melting. The study of the microstructure showed a difference in the depth of the saturated layer, depending on the processing method, during chemical-thermal treatment-1 mm, plasma fusion - 2 mm. The results of measuring the surface micro-hardness showed that, the obtained coating from a mixture of PR-N80X13S2R + Cr2O3 + NH4Cl has a uniform high surface hardness (31-64 HRC), from a mixture of only PR-N80X13S2R - the surface hardness varies in a wide range (15-60 HRC). The study of the microhardness of the cross section of the surface layer showed that, the diffusion region: from a mixture of powder PR-N80X13S2R + Cr2O3 + NH4Cl has uniform hardness (450-490 HV); from a mixture of PR-N80X13S2R - hardness increases in the depth of the molten region (from 300 to 600 HV), and sharply decreases in the heat affected zone (210-170 HV). The use of PR-N80X13S2R alloy powder as the main component in the composition of the paste deposited on the St3 surface during plasma treatment leads to the formation of a doped surface layer with high hardness.

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Low carbon steel with nanostructured surface layer induced by high-energy shot peening

Scripta Materialia ◽

10.1016/s1359-6462(01)00738-2 ◽

2001 ◽

Vol 44 (8-9) ◽

pp. 1791-1795 ◽

Cited By ~ 187

Author(s):

G Liu ◽

S.C Wang ◽

X.F Lou ◽

J Lu ◽

K Lu

Keyword(s):

Surface Layer ◽

Carbon Steel ◽

Shot Peening ◽

Low Carbon Steel ◽

High Energy ◽

Low Carbon ◽

Nanostructured Surface

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THE INFLUENCE OF THE SOAKING TEMPERATURE OF NITRIDED WCL TOOL STEEL (EN-X37CrMoV5-1) ON THE MICROHARDNESS AND TRIBOLOGICAL WEAR OF THE SURFACE LAYER

Tribologia ◽

10.5604/01.3001.0010.6983 ◽

2016 ◽

Vol 268 (4) ◽

pp. 69-78

Author(s):

Michał DWORAK ◽

Adrian BARYLSKI ◽

Krzysztof ANIOŁEK ◽

Elizaveta STEPANOVA

Keyword(s):

Surface Layer ◽

High Temperature ◽

Low Temperature ◽

Tool Steel ◽

Nitrided Layer ◽

Industrial Furnace ◽

Tribological Tests ◽

Nitrided Steel ◽

Hot Work Tool Steel ◽

Soaking Temperature

The present paper refers to the evaluation of the influence of soaking temperature of nitrided hot work tool steel, X37CrMoV5-1 (WCL), intended for dies for extruding aluminium profiles, on the structure, microhardness, and tribological wear of the nitrided layer. The research involved nitrided steel specimens (X37CrMoV5-1) soaked for 8 hours in an industrial furnace at temperatures of 450°C, 480°C, 520°C, 560°C, and 600°C. For comparison purposes, a REFERENCES material was used, which was not soaked after nitriding. Initially, as the soaking temperature raised, the microhardness of the nitrided layer increased by ca. 10%; however, a further increase in the soaking temperature to more than 450°C caused a decrease in the microhardness of the nitrided layer. The results of tribological tests showed that soaking nitrided steel at a low temperature (450°C) and high temperature (600°C) caused a decrease in tribological wear. Out of the tested materials, the highest microhardness of the upper layer was observed in the samples soaked at 450°C, while the highest resistance to tribological wear was obtained for the samples soaked at 600°C. The conducted tests indicate the possibility of extending the lifetime of dies made from the investigated nitrided steel.

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