[MAP Logo] Materials Algorithms Project
           FORTRAN Library

[Image]

Subroutine MAP_STEEL_EDC

  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.

[Image]

Provenance of Source Code

K. Ichikawa (Nippon Steel Corporation) and H.K.D.H. Bhadeshia,
Phase Transformations Group,
Department of Materials Science and Metallurgy,
University of Cambridge,
Cambridge, U.K.

Return to top of Document

Purpose

Estimates the equilibrium partition coefficient.

Return to top of Document

Specification

SUBROUTINE MAP_STEEL_EDC(C,SI,MN,NI,MO,CR,V,&
&KC,KSI,KMN,KNI,KMO,KCR,KV,R,M)

DOUBLE PRECISION C,SI,MN,NI,MO,CR,V,KC,KSI,KMN,KNI,&
&KMO,KCR,KV,R,M

Return to top of Document

Description

The equilibrium partition coefficient for alloy X is given by:-

k0(X) = exp[DeltaoG(X)/(RT)]

where :-
     k0(X) is the equilibrium partition coefficient for alloy element X
     DeltaoG(X) is the Gibbs free energy change per mole that occurs when
     transforming the pure element X from the delta ferrite to the liquid
     state,
     R is the universal gas constant and
     T is the absolute temperature.

The value of k0(C) is assumed to be 1 because of the ready diffusion of
carbon.

The formulae used to calculate the Gibbs free energy changes are:-
     DeltaoG(Si) = 4.187(3.9T - 8200)
     DeltaoG(Mn) = 4.187(-2.308T + 3100)
     DeltaoG(Ni) = 4.187(-0.38T - 2120)
     DeltaoG(Cr) = 4.187(2.19T - 4600)
     DeltaoG(Mo) = 4.187(2.29T - 6600)
     DeltaoG(V) = 4.187(2.3T - 5100)

Return to top of Document

References

1. J.S. Kirkaldy, B.A. Thomson, and E.A. Baganis, Prediction of
multicomponent equilibrium and transformation diagrams for low-alloy steel.
Hardenability concepts with applications to steels., AIME, USA, (1978).

2. L. Smrha, Solidification and crystallisation of steel ingots, SNTL,
Prague, (1983).

Return to top of Document

Parameters

Input parameters

C - real
     C is the carbon concentration (in weight percent).

SI - real
     SI is the silicon concentration (in weight percent).

MN - real
     MN is the manganese concentration (in weight percent).

NI - real
     NI is the nickel concentration (in weight percent).

MO - real
     MO is the molybdenum concentration (in weight percent).

CR - real
     CR is the chromium concentration (in weight percent).

V - real
     V is the vanadium concentration (in weight percent).

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

Output parameters

M - real
     M is the melting temperature of the delta ferrite (in kelvin).

KC - real
     KC is the equilibrium partition coefficient of carbon.

KSI - real
     KSI is the equilibrium partition coefficient of silicon.

KMN - real
     KMN is the equilibrium partition coefficient of manganese.

KNI - real
     KNI is the equilibrium partition coefficient of nickel.

KMO - real
     KMO is the equilibrium partition coefficient of molybdenum.

KCR - real
     KCR is the equilibrium partition coefficient of chromium.

KV - real
     KV is the equilibrium partition coefficient of vanadium.

Return to top of Document

Error Indicators

None.

Return to top of Document

Accuracy

N/A

Return to top of Document

Further Comments

None.

Return to top of Document

Example

1. Program text

       DOUBLE PRECISION C,SI,MN,NI,MO,CR,V,R,M
       DOUBLE PRECISION KC,KSI,KMN,KNI,KMO,KCR,KV
       INCLUDE 'map_constants_gas.f'
       READ (5,*) C,SI,MN,NI,MO,CR,V
       CALL MAP_STEEL_EDC(C,SI,MN,NI,MO,CR,V,&
&      KC,KSI,KMN,KNI,KMO,KCR,KV,R,M)
       WRITE (6,*) KC,KSI,KMN,KNI,KMO,KCR,KV
       WRITE (6,10) M
10     FORMAT (5X,' Assumed melting point of delta ferrite ',F11.4)
       STOP
       END

2. Program data

0.04   0.35   1.0   1.96   0.35   0.38   0.01

3. Program results

1.0000000000000   0.70926988553226   0.74832335748641
0.45478740786807  0.49458284876864   0.82563667673227   0.75812544661665

Return to top of Document

Auxiliary Routines

None.

Keywords

equilibrium partition coefficient, solidification-induced segregation

Download source code

[Image]

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

Contact Information :-

Harry Bhadeshia / hkdb@cus.cam.ac.uk
Hugh Davies / rhd@newton.npl.co.uk
Web site admin. / map@cam.ac.uk

Return to top of Document
Subroutines Index
MAP Homepage

[W3C Wilbur Checked!]
