Tracey Cool*,
Phase Transformations Group,
Department of Materials Science and Metallurgy,
University of Cambridge,
Cambridge, U.K.
*TC is now with the Materials Engineering Department, Parsons Power Generation Systems Ltd, Heaton Works, Shields Road, Newcastle Upon Tyne, NE6 2YL
To estimate the MS temperature of an alloy steel as a function of the free energy, calculated from the chemical composition.
Complete program.
Language: | FORTRAN |
Product form: | Source code |
The program reads in the chemical composition of a steel and thermodynamic results from MTDATA, calculated for a steel of the same composition. It is used here to predict the free energy of austenite, and of ferrite of the same composition, over a range of temperatures. The program calculates the free energy due to the composition of the steel after Ghosh and Olson [2, 3], and the free energy chance for the austenite -> ferrite transformation over the temperature range, including a Zener ordering term. Equating these two values allows the martensite-start temperature to be calculated.
Initial composition, temperature and free energy values are read from a data file, default name ms-profile.dat
MTDATA is a computer based package used for thermodynamic predictions, and is a trademarked product of the National Physical Laboratory.[5]
Note that input parameters are read from a data file, default name ms-profile.dat
A warning is returned if the user attempts to enter an invalid composition. The user is prompted to re-supply the value.
No information supplied.
The data file ms-profile.dat is configured as follows :-
Row 1 J6 Row 2 C(1) Row 3 C(2) Row 4 C(3) Row 5 C(4) Row 6 C(5) Row 7 C(6) Row 8 C(7) Row 9 C(8) Row 10 C(9) Row 11 C(10) Row 12 C(11) Row 13 C(12) Row 14 Y Row 15 J7 Row 16 T(1), D(1), E(1) Row 17 T(2), D(2), E(2) . . . Row n T(n), D(n), E(n)
Complete program
Example of contents of ms-profile.dat
1 0.08 0.43 1.02 2.23 0.71 1.86 0.01 0.03 0 0.008 0.01 0 0 25 973.0000, -7.8159414481E+05, -7.8112221055E+05 948.0000, -7.5085427769E+05, -7.4897941982E+05 923.0000, -7.2071918466E+05, -7.1721440685E+05 898.0000, -6.9117439454E+05, -6.8583476688E+05 873.0000, -6.6220894490E+05, -6.5484851561E+05 848.0000, -6.3381478019E+05, -6.2426412408E+05 823.0000, -6.0598629400E+05, -5.9409055753E+05 798.0000, -5.7871998519E+05, -5.6433731864E+05 773.0000, -5.5201420414E+05, -5.3501449600E+05 748.0000, -5.2586897107E+05, -5.0613281854E+05 723.0000, -5.0028585226E+05, -4.7770371666E+05 698.0000, -4.7526788374E+05, -4.4973939142E+05 673.0000, -4.5081953488E+05, -4.2225289286E+05 648.0000, -4.2694670623E+05, -3.9525820922E+05 623.0000, -4.0365675818E+05, -3.6877036873E+05 598.0000, -3.8095856840E+05, -3.4280555638E+05 573.0000, -3.5886261742E+05, -3.1738124832E+05 548.0000, -3.3738110299E+05, -2.9251636733E+05 523.0000, -3.1652808518E+05, -2.6823146333E+05 498.0000, -2.9631966529E+05, -2.4454892401E+05 473.0000, -2.7677420306E+05, -2.2149322170E+05 448.0000, -2.5791257808E+05, -1.9909120393E+05 423.0000, -2.3975850300E+05, -1.7737243695E+05 398.0000, -2.2233889775E+05, -1.5636961299E+05 373.0000, -2.0568433547E+05, -1.3611903445E+05
Composition of sample 1 Element C Si Mn Ni Mo Cr V Cu W Nb N Co Fe Wt% 0.0800 0.4300 1.0200 2.2300 0.7100 1.8600 0.0100 0.0300 0.0000 0.0080 0.0100 0.0000 93.6120 At fract. 0.0037 0.0085 0.0103 0.0211 0.0041 0.0199 0.0001 0.0003 0.0000 0.0000 0.0004 0.0000 0.9316 700. Centigrade -26.41 J/mol 675. Centigrade -104.92 J/mol 650. Centigrade -196.13 J/mol 625. Centigrade -298.81 J/mol 600. Centigrade -411.90 J/mol 575. Centigrade -534.46 J/mol 550. Centigrade -665.69 J/mol 525. Centigrade -804.86 J/mol 500. Centigrade -951.32 J/mol 475. Centigrade -1104.45 J/mol 450. Centigrade -1263.71 J/mol 425. Centigrade -1428.59 J/mol 400. Centigrade -1598.61 J/mol 375. Centigrade -1773.31 J/mol 350. Centigrade -1952.27 J/mol 325. Centigrade -2135.07 J/mol 300. Centigrade -2321.33 J/mol 275. Centigrade -2510.66 J/mol 250. Centigrade -2702.72 J/mol 225. Centigrade -2897.13 J/mol 200. Centigrade -3093.57 J/mol 175. Centigrade -3291.69 J/mol 150. Centigrade -3491.17 J/mol 125. Centigrade -3691.69 J/mol 100. Centigrade -3892.93 J/mol ***NEW K1*** Predicted free energy due to comp = -1783.1726231491 J/mol Without Zener ordering Ms (new) approximately 374. Centigrade With Zener ordering Ms (new) approximately 374. Centigrade ***OLD K1*** Predicted free energy due to comp = -2109.8726231491 J/mol Without Zener ordering Ms (old) approximately 328. Centigrade With Zener ordering Ms (old) approximately 328. Centigrade No experimental data was provided for comparison
martensite transformation, martensite, start temperature, steel
MAP originated from a joint project of the National Physical Laboratory and the University of Cambridge.
MAP Website administration / map@msm.cam.ac.uk