Effect of the Carbon Content of Low-Alloy Steels on the Surface Quality of Continuous-Cast Semifinished Products and Rolled Plates

Abstract The Fracture evaluation is important in the structural integrity analysis of nuclear equipment which is subjected to the effects of neutron irradiation. The increment of ductile and brittle transition temperature is mainly due to the neutron irradiation, thermal ageing and strain ageing. In addition to above these factors, the high carbon macro-segregation of low-alloy steels also increases the risk of fast fracture failure as the carbon positive macro-segregation will lead to the increasing transition temperature of low-alloy steels. In this work, a relationship between the carbon content and the increment of transition temperature is developed and is used to the fast fracture failure analysis of the highest carbon content region in steam generator channel head. Results show that ratio between the calculated stress intensity factor considering safety coefficient suggested by ASME design code and the critical stress intensity factor is less than one, which indicates a safe design for the highest carbon content region in steam generator channel head.

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Effects of the microstructure of twin roll cast and hot rolled plates on the surface quality of presensitized plates

International Journal of Minerals Metallurgy and Materials ◽

10.1007/s12613-014-0990-x ◽

2014 ◽

Vol 21 (9) ◽

pp. 919-924

Author(s):

Yuan-Zhi Zhu ◽

Ya-Feng Zhang ◽

Chao-Qi Zhao ◽

Feng Zhou

Keyword(s):

Surface Quality ◽

Twin Roll Cast ◽

Hot Rolled ◽

Twin Roll ◽

Rolled Plates

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Formation of Ultrafine Grained Ferrite by Warm Deformation of Tempered Lath Martensite in Low Alloy Steels

Materials Science Forum ◽

10.4028/www.scientific.net/msf.558-559.557 ◽

2007 ◽

Vol 558-559 ◽

pp. 557-562 ◽

Cited By ~ 8

Author(s):

Behrang Poorganji ◽

Takuto Yamaguchi ◽

Tadashi Maki ◽

G. Miyamoto ◽

Tadashi Furuhara

Keyword(s):

Grain Size ◽

Carbon Content ◽

Volume Fraction ◽

Boundary Migration ◽

Lath Martensite ◽

Second Phase ◽

Low Alloy Steels ◽

Warm Deformation ◽

Alloy Steels ◽

Block Width

Microstructure change during warm deformation of tempered lath martensite in Fe-2mass%Mn-C alloys with different carbon contents in the range between 0.1 and 0.8mass%C was investigated. Specimens of the alloys after being quenched and tempered at 923K for 0.3ks were compressed by 50% with a strain rate varying from 10-3 to 10-4s-1 at 923K. EBSD analysis of the deformed microstructures has revealed that fine equiaxed ferrite (α) grains surrounded by high-angle boundaries are formed by dynamic recrystallization (DRX). As carbon content increases, the DRX α grain size decreases. This could be attributed to the change in volume fraction of the cementite (θ) phase as boundary dragging particles. The sub-micron θ particles can suppress the coarsening of the DRX α grains by exerting a pinning effect on grain boundary migration. Furthermore, the fraction of recrystallized region increases by increasing carbon content, presumably due to a decrease in the martensite block width as an initial α grain size and a larger volume fraction of hard second phase (θ) particles. Both of these should increase inhomogeneous plastic deformation which promotes the recrystallization. It seems that continuous DRX is responsible for the formation of ultrafine α grains in the tempered lath martensite.

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Influence of Carbon Content on Surface Quality of Solid-State Sintered SiC Ceramics

International Journal of Applied Ceramic Technology ◽

10.1111/j.1744-7402.2011.02671.x ◽

2012 ◽

Vol 9 (4) ◽

pp. 847-852 ◽

Cited By ~ 5

Author(s):

Jianqin Gao ◽

Jian Chen ◽

Guiling Liu ◽

Yongjie Yan ◽

Zhengren Huang

Keyword(s):

Solid State ◽

Carbon Content ◽

Surface Quality ◽

Sic Ceramics

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Prediction of Microstructure Constituents’ Hardness after the Isothermal Decomposition of Austenite

Metals ◽

10.3390/met11020180 ◽

2021 ◽

Vol 11 (2) ◽

pp. 180

Author(s):

Sunčana Smokvina Hanza ◽

Božo Smoljan ◽

Lovro Štic ◽

Krunoslav Hajdek

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Carbon Content ◽

Deep Understanding ◽

Low Alloy Steels ◽

Isothermal Decomposition ◽

Technical Requirements ◽

Proposed Model ◽

Alloy Steels ◽

Prediction Of Mechanical Properties

An increase in technical requirements related to the prediction of mechanical properties of steel engineering components requires a deep understanding of relations which exist between microstructure, chemical composition and mechanical properties. This paper is dedicated to the research of the relation between steel hardness with the microstructure, chemical composition and temperature of isothermal decomposition of austenite. When setting the equations for predicting the hardness of microstructure constituents, it was assumed that: (1) The pearlite hardness depends on the carbon content in a steel and on the undercooling below the critical temperature, (2) the martensite hardness depends primarily on its carbon content, (3) the hardness of bainite can be between that of untempered martensite and pearlite in the same steel. The equations for estimation of microstructure constituents’ hardness after the isothermal decomposition of austenite have been proposed. By the comparison of predicted hardness using a mathematical model with experimental results, it can be concluded that hardness of considered low-alloy steels could be successfully predicted by the proposed model.

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Study Deformability Ecological Steel (41Cr4)

Materiale Plastice ◽

10.37358/mp.18.3.5029 ◽

2018 ◽

Vol 55 (3) ◽

pp. 357-360

Author(s):

Carmen Otilia Rusanescu ◽

Marin Rusanescu ◽

Florina Violeta Anghelina ◽

Ileana Nicoleta Popescu

Keyword(s):

Heat Treatment ◽

Plastic Deformation ◽

Minimum Degree ◽

Low Alloy Steels ◽

Continuous Cast ◽

External Market ◽

Degree Of Deformation ◽

Resistance To Deformation ◽

Alloy Steels ◽

Low Alloyed Steel

In this paper is studied the hot plastic deformability (plasticity and resistance to deformation) for the low-alloyed steel of heat treatment for mechanical engineering in two ways: compression and tension. Groups of low alloy steels is very important in terms of quality and quantity, the products of these steels have developed internal and external market. The plasticity variation were plotted with the temperature and it was established that the plasticity of the steel increases in the range 700-12000C, then decreases as a result of the firing of the grain boundaries, for the bars obtained from ingot and continuous cast blown it was noticed that the plasticity values are very close. Deformation resistance decreases as the temperature increases. The finest granulation was obtained for a final plastic deformation temperature of 8000C and a minimum degree of deformation of 45%.

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