TCOX14 Elements, Systems, and Phases

This section summarizes the available elements, assessed systems, and assessed phases in the TCS Metal Oxide Solutions Database (TCOX).

Included Elements

There are 34 elements included in the most recent version of the database.

Included Elements
Al	Ar*	B	Ba	C	Ca	Co	Cr	Cu	F
Fe	Gd	H*	Hf	K	La	Li	Mg	Mn	Mo
N	Na	Nb	Ni	O	P	S	Si	Ti	V
W	Y	Yb	Zr
* Ar and H are only included in the gas phase.

Assessed Systems

The most recent version of the database contains assessments of these systems:

• 433 binary and 557 ternary systems in the 34 element framework.
• 294 quaternary systems and 33 higher order systems.

Carbides and nitrides are included in the database. However, neither intermetallic compounds and phases, nor ordered BCC, FCC, and HCP, are included.

For those intermetallic phases not included, and in order for the metallic systems to be accurate to the full range of composition and temperature, phases need to be appended from another database. See TCOX14 Assessed Metallic Systems for suggestions.

The most accurate calculations are obtained in or near these sub-systems and composition ranges.

Assessed Phases

The most recent version of the database contains 744 phases in total.

TCOX14 Models for the Included Phases

When using Console Mode, phases and constituents can be listed in the DATABASE (TDB) module and the Gibbs (GES) module. To show models and constituents for the phases in a chosen system, use the command LIST_SYSTEM with the option CONSTITUENTS in the TDB module.

IONIC_LIQ Phase

The liquid metal and slag (IONIC_LIQ) is described with the ionic two-sublattice liquid model [1985Hil; 1991Sun].

The advantage with the ionic two-sublattice model is that it allows a continuous description of a liquid which changes in character with composition. The model has successfully been used to describe liquid oxides, silicates, sulfides, fluorides as well as liquid short range order, molten salts and ordinary metallic liquids. At low level of oxygen, the model becomes equivalent to a substitutional solution model between metallic atoms.

Different composition sets of IONIC_LIQ designated by #1, #2 etc. (e.g. IONIC_LIQ#1) may be observed, which often represent the metallic and ionized liquid phases. Different composition sets also describe miscibility gaps frequently found in e.g. silicate systems. The #n suffix (where n is an integer) is generated dynamically by Thermo‑Calc when using global minimization and therefore the identification of the phases should be determined from these compositions.

Common Phases for the TCOX Database

Other Phases

The TCOX14 database also contains solid oxides, silicates, fluorides, sulfides, carbides and nitrides, a gaseous mixture phase and solid solution alloy phases (FCC_A1, BCC_A2 etc). Many phases are modeled as solution phases (in all cases where it is meaningful). The solid solution phases such as spinel, mullite, corundum, halite, olivine, fluorite, etc. are modeled within the framework of the Compound Energy Formalism (CEF) [2001Hil].