Process Metallurgy Module for Steel and Slag

Model the complete steelmaking process from scrap to fully refined steel.

The Process Metallurgy Module is an Add-on Module within Thermo-Calc that makes it easy to set up calculations for steel and slag. The module also includes a kinetic model that allows the simulation of the evolution of the steel and slag composition and also the inclusion amount and composition as a function of time based on the actual steelmaking process including alloy or slag additions, blowing of gases into the steel, heating by electric arc and so on.

The module is primarily designed for application to steelmaking and steel refining processes including converters, such as basic oxygen furnaces, electric arc furnaces, ladle furnace metallurgy and more. The module can also be applied to other metallurgical processes.

Designed for the Process Metallurgist

If you work in steel processing or other metallurgical industries, the Process Metallurgy Module can help you better understand your steelmaking and steel refining process. You can optimize your current process parameters or design new steelmaking recipes if you are planning to expand your product portfolio to include new steel grades. 


Questions the Process Metallurgy Module Can Help You Answer:

  • How does the temperature, oxygen partial pressure, slag amount and slag composition influence the sulphur and phosphorus content in the steel?
  • How does the temperature and slag composition influence the fraction of liquid slag?
  • How does the temperature and slag composition influence the slag-line refractory erosion?
  • What is the expected dissolved oxygen [O] in the liquid steel in function of steel making parameters on tapping from the converter or electric arc furnace before deoxidation? What is the expected content of all other elements in the liquid steel?
  • What is the expected dissolved oxygen [O] in the steel after Al- or SiMn-deoxidation?
  • What types and quantity of oxide inclusions are present in the liquid steel after deoxidation?
  • How can these inclusions be altered or modified by alloy or other additions?
  • How is the temperature changed by the process, for example, by oxidation?
  • How does the composition of inblown gas change the temperature?
  • What is the influence of the pressure on the process?
  • What is the composition of the slag after a process?

All of these questions can be investigated both under equilibrium conditions, as well as for a complete kinetic simulation of your steelmaking or -refining process.

Ratio Of Liquid Slag To All Slag In The System Using The Process Metallurgy Module 01

A plot from the Process Metallurgy Module showing the ratio of liquid slag to all slag in the system CaO-Al2O3-SiO2 (blue contour lines) and CaO-10 wt% CaF2-Al2O3-SiO2 (red contour lines) at 1600°C in equilibrium with a steel phase showing the extended liquid region on CaF2 addition.


Several in-depth examples are available that demonstrate how the Process Metallurgy Module can be used at various stages thorughout the steelmaking process. Each example includes a PDF write-up as well as calculation files that can be downloaded and run in Thermo-Calc. 

The Process Metallurgy Module Allows You To: 

  • Simulate the kinetics of the metallurgical process
  • Define steel, slag, ferroalloy compositions and store them in a library for future use
  • Calculate the equilibrium between predefined steels and slags
  • Calculate desulfurization, dephosphorization, decarburization
  • Calculate any partition coefficient
  • Calculate slag characteristics, such as slag basicity or sulphur capacity, viscosity
  • Calculate the fraction of liquid and solid in the slag
  • Calculate under both isothermal conditions (temperature fixed) and adiabatic conditions (temperature changes due to exothermal or endothermal reactions taking place)
  • Calculate the influence of pressure on the reactions taking place. Used for example for the analysis of vacuum treatment.

Thermo Calc Plot Showing Sulphur In Liquid Steel

A plot from the Process Metallurgy Module. The red colors in the upper right-hand corner at high silicon dioxide (SiO2) and aluminium oxide (Al2O3) contents show that the steel contains high amounts of sulfur. This means that only a little of the sulfur in the liquid steel partitioned into the slag phase and tells us that the slag phase has a poor capacity to take up sulphur. The blue colors in the lower left-hand corner indicate that the liquid steel contains only very low amounts of sulfur, so this would indicate a slag composition that is very effective at removing sulfur, or in other words, has a high sulphur capacity.

WEBINAR: Steel Making and Steel Refining using Thermo-Calc and the TCOX9 Database

This in-depth webinar shows you how Thermo-Calc can be applied to steel-making and steel refining using the new Process Metallurgy Module and the TCOX9 thermodynamic database for oxides and slags. The webinar walks you through several examples showing how Thermo-Calc can be used during the steelmaking and steel refining process. 

Watch The Webinar

PUBLICATION: A Kinetic and Thermodynamic Description of the Steel Making Process using Thermo-Calc and the CALPHAD Database TCOX

Read about some of the applications of the Process Metallurgy Module in the recent publication, A Kinetic and Thermodynamic Description of the Steel Making Process using Thermo-Calc and the CALPHAD Database TCOXby A. N. Grundy, M. Powell, R. Rettig, L. Kjellqvist, J. Jeppsson, A. Jansson and J. Bratberg. The paper was published in the Precedings of METEC & 3rd ESTAD 2019, European Steel Technology and Application Days: Düsseldorf, Germany, CCD Congress Center Düsseldorf, 24 - 28 June 2019.

Read The Paper


PUBLICATION: The Application of an Effective Equilibrium Reaction Zone Model Based on CALPHAD Thermodynamics to Steel Making

This paper shows how the Process Metallurgy Module can be used to model the entire steel making process and gives a detailed example using a real case from a steel plant in Ontario, Canda.   

The paper was published as part of the TMS Proceedings 11th International Symposium on High Temperature Metallurgical Processing

Read The Paper 

Easy Workflow for Steel and Slag Calculations

The Process Metallurgy Module makes it easy to define the composition of a steel and slag system because the calculator automatically provides the three common material groups—Steel, Slag and Gas— and provides default composition input types that are relevant to each material group.

You can also save your material compositions right from the calculator and quickly access them in the future. For example, you might want to predefine compositions of steels, ferro-alloys, slags and slag additions. The overall composition of the steel and slag is then obtained by simply adding amounts of these predefined materials. 

Examples for the Process Metallurgy Module

Several example calculations demonstrating some of the uses of the Process Metallurgy Module for steel and slag are included with all new downloads of Thermo-Calc. You can access the examples from within Thermo-Calc in the Help menuExamples Files then click on the folder titled Process Metallurgy. Double-click on an example to load the calculation in Thermo-Calc. There are also videos explaining some of the examples, which are included on this page. 

If you do not have a license for Thermo-Calc 2019b or newer, download a free DEMO version of Thermo-Calc to run the one simplified example included in the DEMO version of the software.

Download Thermo Calc Demo



Request a Free Trial or Quotation for the Process Metallurgy Module

The Process Metallurgy Module, introduced in 2019b, is available for free for all users with a license for TCOX10, TCOX9 and/or TCOX8, and valid Maintenance & Support Subscription (M&SS). If you meet these requirements, your license will automatically include the Process Metallurgy Module.

Fill out the form below to inquire about adding a license for the Process Metallurgy Module to your existing Thermo-Calc license or to request a free trial license of the software.