[MAP Logo]

Materials Algorithms Project
Program Library


Subroutine MAP_STEEL_AA3

  1. Provenance of code.
  2. Purpose of code.
  3. Specification.
  4. Description of subroutine's operation.
  5. References.
  6. Parameter descriptions.
  7. Error indicators.
  8. Accuracy estimate.
  9. Any additional information.
  10. Example of code
  11. Auxiliary subroutines required.
  12. Keywords.
  13. Download source code.
  14. Links.

Provenance of Source Code

H.K.D.H. Bhadeshia,
Phase Transformations Group,
Department of Materials Science and Metallurgy,
University of Cambridge,
Cambridge, U.K.

Top | Next

Purpose

MAP_STEEL_AA3 calculates the paraequilibrium Ae3 temperature as a function of the C, Si, Mn, Ni, Mo, Cr, and V concentration of a low alloy steel.

Top | Next | Prev

Specification

Language:FORTRAN
Product form:Source code

SUBROUTINE MAP_STEEL_AA3(AC,AE3T,R,I1,I2,I3)

DOUBLE PRECISION AC(8),AE3T,R

INTEGER I1,I2,I3

Top | Next | Prev

Description

The method uses a quasichemical thermodynamic model: the Lacher, Fowler and Guggenheim model. See specifically Equation 2 of [1].

Top | Next | Prev

References

  1. H. K. D. H. Bhadeshia and D. V. Edmonds, Acta Metallurgica, 28, (1980), 1265.
  2. H. I. Aaronson, H. A. Domian and G. M. Pound, Trans. AIME, 236, (1966), 753.
  3. G. J. Shiflet, J. R. Bradley and H. I. Aaronson, Metall. Trans. A, 9, (1978), 999.
  4. R. H. Fowler and E. A. Guggenhiem, Statistical Thermodynamics, Cambridge University Press, New York, (1939), 442.
  5. J. R. Lacher, Proc. Cambridge Phil. Soc., 33, (1937), 518.

Top | Next | Prev

Parameters

Input parameters

AC - real array of dimension 8.
AC has 8 elements: the first seven are set to the C, Si, Mn, Ni, Mo, Cr, and V concentrations by weight percent. The eighth element of the array is reserved for the calculation of iron concentration by difference.

R - real
R is the universal gas constant (in joules per mole per kelvin, Jmol-1K-1).

I1,I2 - integers
I1 and I2 define the lower and upper limits for the temperature (in kelvin). Suggested values are I1 = 873K, I2 = 1173K.

I3 - integer
I3 is the temperature interval used in the initial calculation, e.g. I3=30.

Output parameters

AE3T - real
AE3T is the paraequilibrium Ae3 temperature (in deg C).

Top | Next | Prev

Error Indicators

None.

Top | Next | Prev

Accuracy

Within ± 1oC.

Top | Next | Prev

Further Comments

The carbon concentration input must not be less than 0.1 atomic percent.

Top | Next | Prev

Example

To calculate the paraequilibrium Ae3 temperature of a Fe-0.1C-0.1Si-2Mn (by weight percent) alloy.

1. Program text

       DOUBLE PRECISION AC(8), AE3T, R
       INTEGER I, I1, I2, I3
       INCLUDE 'map_constants_gas.f'
       READ(5,*) (AC(I), I=1,7)
       READ(5,*) I1, I2, I3
       CALL MAP_STEEL_AA3(AC, AE3T, R, I1, I2, I3)
       WRITE(6,10) AE3T
       FORMAT(F8.0, ' Centigrade')
       STOP
       END

2. Program data

  0.1    0.1   2.0   0   0   0   0
873   1173    30

3. Program results

768. Centigrade

Top | Next | Prev

Auxiliary Routines

MAP_UTIL_ANALY
MAP_STEEL_OMEGA
MAP_STEEL_AFEG
MAP_STEEL_DAFEG
MAP_STEEL_ENERGY

Top | Next | Prev

Keywords

paraequilibrium temperature, low alloy steel

Top | Next | Prev

Download

Download source code

Top | Prev

MAP originated from a joint project of the National Physical Laboratory and the University of Cambridge.

MAP Website administration / map@msm.cam.ac.uk

Top | Index | MAP Homepage Valid HTML 3.2!