Regression equation for<i>Ar</i><sub>3</sub>temperature for coarse grained as cast steels

Mintz, B.; Banerjee, J.R.; Banks, K.M.

doi:10.1179/030192310x12827375731429

Cited by 17 publications

(19 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(4) for temperature A r3 is significantly more precise in describing the relevant experimental data than the empirical models of other authors [16,32]. The reason is probably its relation to the non-linear dependence of the temperature A c3 = f (C 1/2 ).…”

Section: Discussionmentioning

confidence: 76%

See 1 more Smart Citation

The combined effect of chemical composition and cooling rate on transformation temperatures of hypoeutectoid steels

Schindler¹,

Nemec²,

Kawulok³

et al. 2018

View full text Add to dashboard Cite

The transformation temperatures Ar3 and Ar1 of four unalloyed hypoeutectoid steels with a carbon content of 0.029-0.73 % were determined using dilatometric tests. Unusually high cooling rates of 2 and 8• C s −1 were used intentionally, corresponding to the conditions in the wire rod rolling mills. The developed regression models are phenomenological and allow a simple prediction of transformation temperatures, depending only on the cooling rate and the chemical composition of the steel represented by the carbon equivalent (in the case of Ar1), respectively by the Ac3 temperature (for Ar3). When calculating the Ac3 temperature, it was worth considering its non-linear dependence on carbon content. It has been verified that the derived equations are applicable even at relatively low cooling rates when the austenite decomposes exclusively on ferrite and pearlite.K e y w o r d s : hypoeutectoid steel, carbon equivalent, dilatometer test, cooling rate, decomposition of austenite, transformation temperature

show abstract

Section: Discussionmentioning

confidence: 76%

“…Mintz, Banerjee, and Banks [32] attempted to include the effect of chemical composition, the austenitic grain size in as-cast steels as well as the cooling rate, but at last, they recommended the simplified relationship:…”

Section: Discussion Of Resultsmentioning

confidence: 99%

The combined effect of chemical composition and cooling rate on transformation temperatures of hypoeutectoid steels

Schindler¹,

Nemec²,

Kawulok³

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The chemical composition (mass%) of the steel used in this study is 0.13C, 0.38Si, 1.43Mn, 0.012P, 0.004S, 0.02Nb, 0.002V, 0.018Ti, 0.038Al, and 0.0027N. The dilatometery and formula suggested by Mintz et al12 were used to determine phase transformation temperatures and the results were as follows: A r3 = 695°C, A r1 = 590°C, A c3 = 800°C, and A c1 = 670°C. A r3 and A r1 are the start temperatures of transformation from austenite to ferrite + austenite and from ferrite + austenite to pearlite, respectively, at a constant cooling rate of 3°C S −1 while A c3 and A c1 are the start temperatures of transformation from ferrite + austenite to austenite and from pearlite to ferrite + austenite, respectively, at a constant heating rate of 0.3°C S −1 .…”

Section: Methodsmentioning

confidence: 74%

Effect of the Charging Temperature on the Hot Ductility of Nb‐Containing Steel in the Simulated Hot Charge Process

Wang

et al. 2012

steel research int.

View full text Add to dashboard Cite

In order to develop a comprehensive understanding of the effect of hot charging temperature on the hot ductility of a Nb‐containing steel, direct hot charging process was simulated by using a Gleeble thermo stress/strain machine. Three kinds of thermal histories were introduced to assess the hot ductility of the steel during continuously cast, hot charging, and cold charging process by means of hot tensile test in relation to surface cracking of hot charging processed steel slabs. The ductility of the specimens charged at the temperature within the range of ferrite/austenite two‐phase region and charged at the temperature just below the Ar1 of the steel is largely reduced. These results can be ascribed to the retained ferrite films at the boundaries of austenite encouraging voiding at the boundaries and these voids gradually link up to give failure around 750°C, and the combination of inhogeneous austenite grain size and precipitations aggravating the ductility trough by encouraging grain boundary sliding at 950°C. The steel via the conventional cold charge process experienced a complete phase transformation from austenite to ferrite and pearlite structure during the cooling to the ambient temperature. This steel can be charged into a reheating furnace and rolled without experiencing hot embrittlement due to the recrystallization and the precipitates are trapped inside a newly formed grain of austenite. In comparison with the hot ductility results, the hot tensile strength is only slight influenced by the charging temperature.

show abstract

“…It is known that both Al and Nb additions encourage the formation of martensite so particular care has to be taken when both alloying additions are present and high cooling rates are used during processing [3,[6][7][8]. A recent study [6] has shown that Nb containing steels are more exposed to martensite formation leading to the creation of local brittle zones and influencing overall toughness and it is known that Nb lowers the transformation temperatures [7,8].…”

Section: Discussionmentioning

confidence: 99%

“…Previous work [9] has also shown that Nb containing steels can give coarser carbides as well as an increase in their density, both of which cause a deterioration in impact performance. The thickness of the grain boundary carbide has been shown to be dependent on the temperature of the pearlite reaction [10] and this depends on both the grain size and the presence of Nb, as can be seen from the following empirical equation for the Ar3, [8],…”

Section: -4mentioning

confidence: 99%

Hot rolled high Al containing steels as a replacement for the control rolled high strength low alloy (HSLA) steels

Qaban¹,

Mintz²,

Naher³

2017

AIP Conference Proceedings

View full text Add to dashboard Cite

The extent to which Al and Nb can be used to improve the properties of hot rolled steels has been investigated with the aim of obtaining mechanical properties similar to those given by the more expensive, control rolled or normalised route, eg. API X52 line pipe. Three steels with 0.02%Al, 0.16%Al and 0.16%Al, 0.018%Nb have been examined and their strength and impact behaviour obtained. The 0.16%Al steel had a similar strength to the 0.02%Al containing steel~300MPa, but better impact behaviour (30-40°C lower 54J, ITT) with an impact transition temperature (ITT) of-90°C which from previous work will be due to a refinement of the grain boundary carbides. The present work shows that the addition of Nb to this high Al containing steel, although beneficial to strength, giving a lower yield strength (LYS) of 385 MPa, close to that given by some of the control rolled steels gives very poor impact behaviour with a 54J ITT of only-20°C. The improvement of strength is mainly a result of precipitation hardening by NbCN with some benefit from grain refinement while the deterioration of impact behaviour might be due to the presence of lower transformation products or coarser carbides. Further work is required to positively clarify the cause of this deterioration and to explore further options in achieving the aim of obtaining a hot rolled steel with strength in the range 350-400MPa and 54J ITT of-50°C.

show abstract

Regression equation forAr₃temperature for coarse grained as cast steels

Cited by 17 publications

References 7 publications

The combined effect of chemical composition and cooling rate on transformation temperatures of hypoeutectoid steels

The combined effect of chemical composition and cooling rate on transformation temperatures of hypoeutectoid steels

Effect of the Charging Temperature on the Hot Ductility of Nb‐Containing Steel in the Simulated Hot Charge Process

Hot rolled high Al containing steels as a replacement for the control rolled high strength low alloy (HSLA) steels

Contact Info

Product

Resources

About

Regression equation forAr3temperature for coarse grained as cast steels

Cited by 17 publications

References 7 publications

The combined effect of chemical composition and cooling rate on transformation temperatures of hypoeutectoid steels

The combined effect of chemical composition and cooling rate on transformation temperatures of hypoeutectoid steels

Effect of the Charging Temperature on the Hot Ductility of Nb‐Containing Steel in the Simulated Hot Charge Process

Hot rolled high Al containing steels as a replacement for the control rolled high strength low alloy (HSLA) steels

Contact Info

Product

Resources

About

Regression equation forAr₃temperature for coarse grained as cast steels