S.J. Jones* and H.K.D.H. Bhadeshia,
Phase Transformations Group,
Department of Materials Science and Metallurgy,
University of Cambridge,
Cambridge, U.K.
*Dr S.J. Jones is now with Ford Motor Co. (UK) Ltd
To calculate the soluble boron, soluble nitrogen and boron nitride content of austenite at any temperature.
Language: | FORTRAN |
Product form: | Source code |
SUBROUTINE MAP_STEEL_SOL_BOR(BATM,BWT,NITATM,NITWT,NIT2,TEMPC, & BSOL,BWTSOL,NITSOL,NITWTSOL,NITB,BNIT) IMPLICIT NONE DOUBLE PRECISION BATM,BWT,NITATM,NIT2,NITWT,TEMPC, & BSOL,BWTSOL,NITSOL,NITWTSOL,NITB,BNIT,NIT3,CONST, & BWTSOLMAX,SOLPRODCON,DIFBATMNIT2,SQROOT,NIT3A,NIT3B
If there is only boron, all of this is assumed to remain in solution, whilst if there is only residual nitrogen (that nitrogen present after reacting with titanium to form TiN), all of this is assumed to remain in solution.
If both residual nitrogen and boron are present, then a solubility product is used to determine whether all the boron and nitrogen can remain in solution. This is determined by assuming that all the residual nitrogen enters solution and calculating the maximum possible soluble boron concentration. This is then compared with the actual boron concentration.
If the actual boron concentration is less than the maximum calculated, then all the boron and all the residual nitrogen can be remain in solution simultaneously. However, if the actual boron concentration is greater than the maximum calculated, then all the boron and the residual nitrogen cannot remain in solution simultaneously and boron nitride will precipitate. By assuming that the stoichiometry of this is represented by BN then it is possible to calculate the soluble boron by determining the positive root of the following equation which is constructed using the solubility product due to Maitrepierre et al. [2]:-
where :-
The number of moles of boron per unit mass of steel forming BN is therefore given by mass balance as :-
The number of moles of soluble nitrogen per unit mass of steel is thus :-
None.
No information supplied.
None.
PROGRAM MAP_STEEL_SOL_BOR IMPLICIT NONE C DOUBLE PRECISION BATM,BWT,NITATM,NIT2,NITWT,TEMPC, & BSOL,BWTSOL,NITSOL,NITWTSOL,NITB,BNIT C READ(*,*) BATM,BWT,NITATM,NITWT,NIT2,TEMPC C CALL MAP_STEEL_SOL_BOR(BATM,BWT,NITATM,NITWT,NIT2, & TEMPC,BSOL,BWTSOL,NITSOL,NITWTSOL,NITB,BNIT) C WRITE(*,10) BSOL,BWTSOL,NITSOL,NITWTSOL,NITB,BNIT 10 FORMAT(E10.3,1X,E10.3,1X,E10.3,1X,E10.3,1X,E10.3,1X,E10.3) C STOP C END
0.370E-5 0.400E-2 0.357E-5 0.500E-2 0.250E-2 0.940E3
0.126E-08 0.136E-05 0.250E-02 0.350E+01 0.370E-05 0.370E-05
None.
solubility product, boron, nitrogen, austenite, steel, boron nitride, temperature
MAP originated from a joint project of the National Physical Laboratory and the University of Cambridge.
MAP Website administration / map@msm.cam.ac.uk