FactSage 6.1 (2009)

• In the Reactants Window a new option has been added that automatically calculates the amount to balance reactants in a given stream. For example, let us say the reactants in steel stream #1 are '100 Fe + 0.1 C + 18 Cr' (or in oxide stream #2 are '1 CaO + 0.40 SiO2 + 0.05 Cr2O3'). Entering '? 100' for the amount of Fe ('? 1' for the amount of CaO) causes the program to calculate and specify the balance 81.9 Fe (0.55 CaO).

• In the Reactants Window the 'Edit' drop down menu now includes an option where all the reactants can be automatically re-ordered by increasing (or decreasing) amounts or molecular weights, or by stream #, or re-written in the corresponding amounts of the elements.

• In the Menu Window, the Parameters Window has been reformatted - see the Phase Diagram module.

• In the Menu Window, checking 'include molar volumes' now displays additional data in the calculated output such as densities, etc.

• In the Menu Window new solidification algorithms have been added that list the details during the cooling calculations (Equilibrium or Scheil) including the phase and component compositions and amounts at the various transition temperatures. With the new method of storing intermediate results it is now possible to keep track of the solidification of a particular phase at each stage of the solidification process. Thus the user is enabled to see how this phase is distributed among the primary crystallisation products, as a precipitate inside other solid grains which have formed at intermediate stages, or in the final eutectic structure that is formed when solidification is finished.

  The numerical results of the calculations can be post-processed for plotting in the usual way. The following graph shows the 'fraction solid' plot including both the Scheil and the Equilibrium curve.

  The results from the calculation may also be used in another way in order to keep track of the various phases which are formed in the different temperature ranges. In the Summary screen the phases listed in conjunction with the various constituents (phase assemblages) can be used as direct input for further equilibrium calculations. By pointing and clicking product phases can be recycled through the calculation. This is particularly useful when investigating the behaviour of castings of complex alloy systems. See also example #16 in the Advanced Equilib examples.

• In the Results Window the FACT format has been completely revamped. For example, supplementary data are provided for the gas phase and stable solutions, solutions are ordered with respect to stability, quantities are aligned on the left, full names up to 40 characters (was truncated to 28) are listed for the compound species, etc. When 'initial conditions' is checked (see Reactants Window) both integral and delta integral (ex: H and Delta H, Cp and Delta Cp, etc.) values are now reported.

• In the Results Window the Cp includes both the contribution from the stoichiometric sum of the Cp values of all phases and as well as (this is new) the change in phase amounts within the phase assemblage.

• The Slide Show has been edited to reflect new additions in FactSage 6.1 including the reformatted Results output.

• Fact-XML

  In the Equilib Results Window click on the XML Icon (or click on 'Output > Run Fact-XML ...'). Extensive changes and additions have been carried out, including

  • the 10 most recent custom compositions are now saved
    
  • properties such as Eh, Ph, Osmotic coefficient, molality, ionic strength, magnetic moment, critical temperature can be plotted
    

  • up to 10 multiple functions on the same graph can be plotted
    
  • there is a new activity cut-off limit for solutions
    

  • the number of significant digits for thermodynamic data of phases can now be changed
    
  • custom selection of composition variables. Sometimes the composition of a solution phase in the output of the Equilib module is expressed in terms of unusual, unwieldy or odd-looking components. The XML output now permits you to define the components you prefer.

FactSage 6.2 (2010)

• Non-Stoichiometric Compounds - Most reactants specified in the Reactants Window are stoichiometric compounds such as H₂O or SiO₂. However some compounds stored in the public compound databases may be non-stoichiometric. Such compounds are identified in the Reactants Window by their nominal stoichiometric formula that is close in composition to the real values.

  For example, in the FACT53 compound database the non-stoichiometric compound Fe(7.016)S(8) (e.g. 7.016 Fe, 8 S) is identified by its nominal stoichiometric formula Fe7S8; Zn(2.001)Ca(0.9999) is Zn2Ca; Fe(10.99992)S(12) is Fe11S12; etc. When such a compound (e.g. the nominal composition Fe7S8, Zn2Ca, Fe11S12, ...) is entered as a reactant it is 'flagged' by a yellow mask in the Reactants Window as being non-stoichiometric (for this to occur the 'initial conditions' box must be checked).

  Sometimes a non-stoichiometric compound has more than one phase. For example, in the SGPS (SGTE) compound database, wustite Fe(0.947)O(1) has the nominal composition FeO and data are stored for both the solid and the gas phase. But the stored composition for the gas phase is for the nominal composition (FeO) since a non-stoichiometric gas molecule cannot exist.

  For a non-stoichiometric compound in Equilib and Phase Diagram
  

  • the solid and liquid phases are treated as non-stoichiometric as defined by the real composition

  • the gas and aqueous phases are treated as stoichiometric as defined by the nominal composition

• Solidification Software - examples of solidification calculations for Scheil-Gulliver cooling hve been added to the slide shows.

• FToxid-SLAG Information - In the Menu Window of Equilib and Phase Diagram, when selecting an FToxid solution slag phase (FToxid-SLAGA, FToxid-SLAGB, etc.) additional information about the slag phase is now posted in order to help you decide which slag (SLAGA, SLAGB, etc.) should be selected.

  Most calculations with FToxid-SLAG use FToxid-SLAGA - this is the slag solution with all the oxides and includes up to 10% sulfur if this element is also included in the calculation.

  The other slag phases are:

  FToxid-SLAGB with SO4;      FToxid-SLAGC with PO4;     FToxid-SLAGD with CO₃;
  FToxid-SLAGE with H₂O/OH;     FToxid-SLAGF with I;      FToxid-SLAGG with C/N/CN;
  FToxid-SLAGH with F/Cl;      FToxid-SLAG? - all species (not recommended).

  More extensive details on the FToxid-SLAGA, -SLAGB, etc. phases can be found in the Documentation located in the FactSage Main Menu.

• Miscibility Gap - Option 'I' - In the Menu Window of Equilib and Phase Diagram, when selecting solution phases it is necessary to indicate which phases may have miscibility gaps. This is done by specifying option 'I' (or 'J') for possible 2-phase (or 3-phase) immiscibility.

  If 'I' is not selected and a calculated composition is within or near a miscibility gap, then the composition will most likely be in error. If 'I' is selected but there is no miscibility gap, the calculated composition will be correct but the time to calculate will be increased. In other words, selecting 'I' is a safe way but possibly time consuming especially when several phases are incorrectly designated as 'I' when '+' would suffice.

  In order to determine if option 'I' should be used it has been necessary to consult the documentation. For example, in FToxid database the following phases may have regions of 2-phase or 3-phase immiscibility: FToxid-SLAG, -mullite, -spinel, -monoxide, -pyroxenes, -olivine, -corundum, -ilmenite. Prior to 6.2 such phases when selected were automatically set to option 'I'. But within a given solution, there will only be a miscibility gap when certain elements are present. For example, in the FToxid-MeO monoxide phase that contains FeO, CaO, MgO, MnO, NiO, CoO, etc. only those solutions containing CaO could have a miscibility gap.

  In FactSage 6.2 the precise conditions for option 'I' are now stored within the FToxid, FTmisc (for sulphide systems) and FTsalt databases. Equilib and Phase Diagram will automatically select option '+' when immiscibility is not possible, and set it to 'I' for those cases where option 'I' should be used. It is no longer necessary to consult the documentation - the selection of '+' or 'I' will be done for you. We consider this to be a very important and useful improvement to the Equilib and Phase Diagram modules.

  Note: you are can overide the default 'I' setting by manually selecting '+' but this is not recommended.

• Miscibility Gap - Output The output for immiscible phases (options 'I' and 'J') in the Results Window has been reformatted. The list of solution phases in the output is normally ordered with respect to amount and then by 'activity' for those phases with zero amounts. This means that the stable ('activity' = 1) and prominent solutions appear at the top.

  In FToxid-SLAGA for example, this may result in Slag-liquid#1 appearing in the list at the top, far away from Slag-liquid#2 which would be at the bottom if it is not stable.

  In FactSage 6.2 both immiscible phases for the same solution phase (e.g. Slag-liquid#1 and Slag-liquid#2) will now appear together - the position in the list is determined by the amount (or activity) of the more prominent immiscible phase.

• Heating and Cooling - A range of values such as alpha, temperature, pressure, etc. is specified in the 'Final Conditions' frame in the Menu Window as 'first-value last-value step' where 'step' is the step in the calculation or optionally left blank.

  A range of alpha (pressure, etc.) can be increasing, for example '0 1 0.2' (e.g. 0 0.2 0.4 ... 1), or decreasing, for example ' 1 0 0.2' (e.g. 1 0.8 0.6 ... 0). However the temperature range is an exception and has always been treated as increasing. For example the temperature range '3000 1000 500' (e.g. 3000 2500 ... 1000) would be treated as '1000 3000 500' (e.g. 1000 1500 ... 3000).

  In FactSage 6.2 the temperature range may now be for heating ('1000 3000 500') or for cooling ('3000 1000 500') and the output in the Results Windows respects the direction in temperature. The cooling option is useful when identifying the first solids precipitated as shown next.

• Phase Transitions - When a range of alpha, temperature or pressure, etc. is specified in the Menu Window the 'Transitions' button in the 'Equilibrium' frame can be selected and Equilib will then calculate all phase transitions within the specified range. For multiphase calculations the number of such phase transitions may be extensive and difficult to identify especially when the results are mixed in with the output generated by a large range of 'First-value Last-value Step'.

  The Equilibrium 'transitions' button has been replaced by two buttons:

  • 'normal + transitions' reports all calculations and all phase transitions - this is as before

  • 'transitions only' only reports the phase transitions - this is new.

  When a transitions button is pressed, a 'Transitions frame' is displayed in the Menu Window and the 'number of transitions' can now be specified. You can specify 'All' to list all the transitions (just as before), or you can limit the number of reported transitions to 1, 2, or 3 etc. as you wish.

  When combined with the 'heating' or 'cooling' temperature range described earlier, this means that you need only calculate the first 1, 2 or 3 etc. transitions on cooling down from a high temperature (e.g. the liquidus for the first precipitate, etc.) or the first 1, 2, or 3 etc. transitions on heating up from a low temperature.

• Volume Unit - litre or dm3 - A litre (or liter), l or L, is a volume equivalent to a cubic decimetre, dm3; a millilitre (or milliliter), ml, is a volume equivalent to a cubic centimetre cm3. The output in the Results Window has been reformatted: in the FACT output the volume unit is 'litre'; in the ChemSage output the volume unit is 'dm3'.

• Viscosity and Thermal Conductivity of Gases - some of the physical properties reported in Results Window are calculated by a module called PhysProp.dll that is accessed by Equilib. In FactSage 6.2 there is a new version of PhysProp.dll that now calculates an estimation of the viscosity and thermal conductivity of the gas phase. In order to activate this calculation the 'include molar volumes' box located in the Menu Window must be checked.

FactSage 6.3 (2012)

FactSage 6.4 (2013)

• Load last system ?

  When you first run Equilib then a summary of 'Current Databases Selected' and 'Current Data Search Options' is posted and you are asked if you want to 'Load last system ?'.

  If you reply 'Yes' then the last Equilib system is loaded as in previous versions.

  If you reply 'No' you now have the the option to keep the current 'Databases Selected' and 'Data Search Options', or, clear the 'Databases Selected', apply default settings to 'Data Search Options' and open the 'Data Search Window'."

  Compound Species Selection - see Slide Show 'Equilib - Regular Features - Section 19' There is a new default exclusion of species from compound species selection When two or more databases are connected, the same species may appear in more than one database. In such cases, a species should generally only be selected from one database. Otherwise conflicts will probably occur. In order to assist users in deciding which species to exclude, the FactSage developers have assigned priorities. When you initially click on "pure solids", "pure liquids", or "gas" you may now see that several species marked with an "X" have not been selected. That is, they have been excluded by default because of probable conflicts between databases. The FactSage developers suggest that these species not be selected for this particular calculation. If you wish to select species marked with an "X" you must first click on 'permit selection of "X" species'. This will then override the default setting and permit you to select species as in FactSage 6.3. This will also activate the 'suppress duplicates' button and enable you to define a database priority list as in FactSage 6.3. IMPORTANT : For many calculations, it may frequently be advisable or necessary to de-select other species in addition to those marked with an "X." - refreshing compound default selection - This message will appear whenever you change the selected databases, or change the 'Data Search Options', or change the components; that is any action that requires the databases to be re-scanned. The purpose of the message is to simply advise you that the compound species selection may have changed. The message will not appear when you load a new system or when you load a stored file.

• Paraequilibrium calculations - paraequilibrium checkbox, edit button (see screenshot below)
  - see Slide Show 'Equilib - Advanced Features - Section 14'

  Paraequilibrium refers to the concept that diffusion kinetics of interstitial solutes is much faster than that of substitutional solutes. For example in the Fe-Cr-C system carbon diffuses and equilibrates rapidly whereas the diffusion of Fe and Cr between solid phases is slow and could be ignored.

  A new paraequilibrium checkbox that performs paraequilibrium calculations is now offered in the Equilibrium Menu Window. In addition an Edit button opens an input box where the diffusing solutes (typically elemental carbon) are defined.

  An example of parequilibrium calculations in the Fe-Cr-C system is presented later in the Phase Diagram section.

  

  It is also possible to calculate the single phase with the minimum Gibbs energy for any given set of input conditions. Such calculations may be of practical interest in physical vapour deposition where deposition from the vapour phase is so rapid that phase separation cannot occur, resulting in a single-phase solid deposit.

• Selected Species - set in the 'Menu Window (see screenshot above)

  Prior to 6.4 the maximum number of selected species and the maximum number of selected phases was 1500. In FactSage 6.4 the maximum number of selected species is 3000.

  Both total selected species and total selected phases are now posted in the Menu Window.

• Print cut-off

  The Print cut-off is set in the Parameters Window and limits the length of output in the Results Window. It only affects the display; it has no effect upon the calculation. In the Results Window there are two types of displays - FACT Format and ChemSage Format. You can display either or both Formats. This is done by clicking on 'Output > Format > ...'. The cut-off value is in the range 1e-75 to 0.01 and indicates the lower cut-off limit for phase activities and solute concentrations. It does affect the display of solution end-members. In FactSage 6.4 there is new 'Show only stable phases' button. When checked only the stable product phases are displayed. Click on the 'Help' button for more information

• CooLing Calculation Window - option L, T-auto checkbox, cooling gases

  To display the solution extended menu point to the '+' column of the solution (Equilib Menu Window) and then click on the mouse-right-button. The Scheil target calculation (option S) and the solidification calculations (option D that offered either Scheil or Equilibrium cooling) have been replaced by the one single option L - the cooLing calculation.

  Solution extended menu - FactSage 6.3

  Solution extended menu - FactSage 6.4

  Option L can be assigned to any solution phase (including the gas phase). However cooling is most meaningful when the initial solution is a liquid since the cooling calculations relate to solidification. When option L is assigned to a solution phase you are presented with a new Cooling Calculation Window. equilibrium cooling - calculates the results using the normal Equilibrium calculation The total mass remains unchanged throughout the calculations. Any solid solution could change its compositions during cooling since it remains in equilibrium with the other phases. Scheil-Gulliver cooling - as phases precipitate from the option L solution phase they are dropped from the total mass balance and their compositions do not change. normal equilibrium - quits the cooling calculations and returns you to the regular Equilib calculations. In the Cooling Calculation Window you can also display the transitions and summary pages in the Results Window (this was not available for equilibrium cooling).

  Prior to 6.4 for solidification calculations it was necessary to provide an initial starting temperature (for example 1600°C) in the temperature Final Conditions input box. For meaningful solidification calculations this would be a value where the solution phase (for example SLAG) is 100% liquid. In 6.4 a new T-auto checkbox is now available. By checking T-auto the starting temperature is now automatically calculated by the program (internally Equilib performs a precipitate target calculation to identify when the first phase is formed). The actual starting value is rounded up to comply with the cooling step. For example, if solidification first starts at 1580.23°C then a cooling step of 10°C (or 25°C) would set the starting temperature at 1590°C (or 1600°C). If the starting temperature cannot be calculated then the value defined in the Final Conditions (1600°C) is used instead.

If the cooling phase is the gas phase then the precipitates could be any or all of the other compound and solution phases. To activate the gas phase, first select the gas species in the usual way. Then with the mouse-right-button click on the gas '+' checkbox in the compound species frame of the Menu Window - this will open the Species Selection window. Point to the '+' column of any selected gas species and then click with the mouse-right-button and assign option L.
• Duplicate gas species

  When the gas phase from more than one database is selected there may be duplicate entries for gas species. In such a case the calculated equilibrium will be incorrect.

  In FactSage 6.4 a warning message is now issued when duplicates gas species are detected and the offending species are flagged with '_d'.

  

  Duplicates can be avoided by checking the 'suppress duplicates' checkbox in the Menu Window .

• Results Window

  Traditionally the maximum length of a line in the Results Window has been limited to 80 characters. In FactSage 6.4 this restriction is no longer applied and some of the results, particularly the display in the ChemSage Format, have much longer lines.

  To accommodate the expanded output the size of the window display can be increased by pointing to the borders and stretching the edges of the Window. In addition the font size of the display can be changed by clicking on the screen. Enter Ctrl+ to increase font size, Ctrl- to decrease the font size and Ctrl 0 to return to the default setting. Both font size and Window display size are retained next time Equilib is run. To return to the original settings go to the Edit toolbox menu and click on 'Default font wnd Window size'.

FactSage 7.0 (2015)

• Units Window

  Click on the units menu to enter the Units Window you can select either 'Metric SI units' or 'English units'. For example:

  SI units: T(K), P(bar), Energy(J), Mass(mol), Volume(litre)
  English Units: T(F), P(psi), Energy(BTU), Mass(lb), Volume(Ft3)

  In FactSage 7.0 it is now possible to mix the units and select various combination, for example :

  T(F), P(psi), Energy(kwh), Mass(lb), Volume(Ft3)
  T(C), P(psi), Energy(kwh), Mass(lb), Volume(Ft3)
  T(C), P(psi), Energy(kwh), Mass(mol), Volume(Ft3)
  T(K), P(Pa), Energy(J), Mass(lb), Volume(litre)

FactSage 7.1 (2017)