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H.K.D.H. Bhadeshia,

Phase Transformations Group,

Department of Materials Science and Metallurgy,

University of Cambridge,

Cambridge, U.K.

To calculate the differential (w.r.t. the carbon concentration at the T0 boundary) of the free energy change accompanying the transformation from austenite to ferrite of the same chemical composition.

Language: | FORTRAN |

Product form: | Source code |

FUNCTION MAP_STEEL_G91(XTO,T,W,W1,H1,S1,F,H,S,AJ,AJ1,R)

DOUBLE PRECISION XTO,T,W,W1,H1,S1,F,H,S,AJ,AJ1,R

MAP_STEEL_G91 calculates the differential (with respect to the carbon concentration at the T0 boundary) of the free energy change accompanying the transformation from austenite to ferrite of the same chemical composition.

- C. Zener, Trans. AIME,
__167__, (1946), 550. - J.C. Fisher, Metals Transactions,
__185__, (1949), 688-690. - H.K.D.H. Bhadeshia and D.V. Edmonds, Acta Metallurgica,
__28__, (1980), 1265-1273.

**XTO**- real- XTO is the carbon concentration at the T0 boundary.
**T**- real- T is the temperature (in kelvin).
**W**- real- W is the carbon-carbon interaction energy in austenite (in joules per mole, Jmol
^{-1}). **W1**- real- W1 is the carbon-carbon interaction energy in ferrite (in joules per mole, Jmol
^{-1}). **H1**- real- H1 is the excess partial molar enthalpy of solution of carbon in ferrite (in joules per mole, Jmol
^{-1}). **S1**- real- S1 is the excess partial molar entropy of solution of carbon in ferrite (in joules per mole per kelvin, J mol
^{-1}K^{-1}). **F**- real- F is the energy.
**H**- real- H is the excess partial molar enthalpy of solution of carbon in austenite (in joules per mole, Jmol
^{-1}). **S**- real- S is the excess partial molar entropy of solution of carbon in austenite (in joules per mole, Jmol
^{-1}). **AJ**- real- AJ = 1 - e
^{(W/RT)}, where R is the universal gas constant. **AJ1**- real- AJ1 = 1 - e
^{(W1/RT)}, where R is the universal gas constant. **R**- real- R is the universal gas constant (in joules per mole per kelvin, Jmol
^{-1}K^{-1})

**MAP_STEEL_G91**- real- MAP_STEEL_G91 is the differential of MAP_STEEL_FTO1.

None.

No information supplied.

None.

DOUBLE PRECISION XTO,T,W,W1,H1,S1,F,H,S,AJ,AJ1,R,XG91 DOUBLE PRECISION MAP_STEEL_G91 INCLUDE 'map_constants_gas.f' READ (5,*) H,S,H1,S1,W,W1 READ(5,*) XTO,T,F,AJ,AJ1 XG91=MAP_STEEL_G91(XTO,T,W,W1,H1,S1,F,H,S,AJ,AJ1,R) WRITE (6,*) XG91 STOP END

None supplied.

None supplied.

None.

carbon, T0 boundary, austenite, ferrite

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