skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Thermodynamic prediction of the eutectoid transformation temperatures of low-alloy steels

Abstract

The experimental eutectoid transformation temperatures (A{sub 1}) of low-alloy steels, as reported in the USS Atlas of I-T diagrams, have been compared to the thermodynamic predictions of a model proposed by Kirkaldy and Venugopalan. The analysis is consistent with the model prediction that Cr atoms are almost fully partitioned, while Ni and Mo atoms are scarcely partitioned, during the eutectoid transformation. This study also shows that Mn atoms are partitioned fully or partly in C-Mn, Cr-Mn, and Mo-Mn steels, while they are scarcely partitioned in Ni-Mn steels. The difference ({Delta}T) between the orthoequilibrium (OE) eutectoid temperature (A{sub e1}) and the paraequilibrium (PE) eutectoid temperature (A{sub p1}) has been investigated as a function of the content of each substitutional alloying element. The slope of {Delta}T increases with substitutions of Mo, Ni, Mn, Si, and Cr, with Mo having the least effect, Ni the next-greatest effect, and so on. Considering both Mn partitioning and the slope of {Delta}T, the equation for the prediction of A{sub 1} temperatures of low-alloy steels proposed by Kirkaldy and Venugopalan is modified. This new equation is in better agreement with the experimental A{sub 1} temperatures.

Authors:
;  [1]
  1. Colorado School of Mines, Golden, CO (United States). Div. of Engineering
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
684451
Resource Type:
Journal Article
Journal Name:
Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science
Additional Journal Information:
Journal Volume: 30; Journal Issue: 9; Other Information: PBD: Sep 1999
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTAL-PHASE TRANSFORMATIONS; LOW ALLOY STEELS; EUTECTOIDS; THERMODYNAMIC MODEL; CHEMICAL COMPOSITION; PREDICTION EQUATIONS

Citation Formats

Lee, Y.K., and Lusk, M.T. Thermodynamic prediction of the eutectoid transformation temperatures of low-alloy steels. United States: N. p., 1999. Web. doi:10.1007/s11661-999-0241-3.
Lee, Y.K., & Lusk, M.T. Thermodynamic prediction of the eutectoid transformation temperatures of low-alloy steels. United States. doi:10.1007/s11661-999-0241-3.
Lee, Y.K., and Lusk, M.T. Wed . "Thermodynamic prediction of the eutectoid transformation temperatures of low-alloy steels". United States. doi:10.1007/s11661-999-0241-3.
@article{osti_684451,
title = {Thermodynamic prediction of the eutectoid transformation temperatures of low-alloy steels},
author = {Lee, Y.K. and Lusk, M.T.},
abstractNote = {The experimental eutectoid transformation temperatures (A{sub 1}) of low-alloy steels, as reported in the USS Atlas of I-T diagrams, have been compared to the thermodynamic predictions of a model proposed by Kirkaldy and Venugopalan. The analysis is consistent with the model prediction that Cr atoms are almost fully partitioned, while Ni and Mo atoms are scarcely partitioned, during the eutectoid transformation. This study also shows that Mn atoms are partitioned fully or partly in C-Mn, Cr-Mn, and Mo-Mn steels, while they are scarcely partitioned in Ni-Mn steels. The difference ({Delta}T) between the orthoequilibrium (OE) eutectoid temperature (A{sub e1}) and the paraequilibrium (PE) eutectoid temperature (A{sub p1}) has been investigated as a function of the content of each substitutional alloying element. The slope of {Delta}T increases with substitutions of Mo, Ni, Mn, Si, and Cr, with Mo having the least effect, Ni the next-greatest effect, and so on. Considering both Mn partitioning and the slope of {Delta}T, the equation for the prediction of A{sub 1} temperatures of low-alloy steels proposed by Kirkaldy and Venugopalan is modified. This new equation is in better agreement with the experimental A{sub 1} temperatures.},
doi = {10.1007/s11661-999-0241-3},
journal = {Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science},
number = 9,
volume = 30,
place = {United States},
year = {1999},
month = {9}
}