Thermodynamic description of reactions between Mg and CaO

Research output: Contributions to collected editions/worksArticle in conference proceedingsResearchpeer-review

Authors

  • Rainer Schmid-Fetzer
  • Artem Kozlov
  • Björn Wiese
  • Chamini L. Mendis
  • Domonkos Tolnai
  • Karl U. Kainer
  • Norbert Hort

CaO is considered as possible replacement for cover gases such as SF6 during melting and casting of Mg alloys. Such CaO additions to molten Mg increase the ignition resistance by forming a protective oxide layer. The actual reactions between liquid Mg and CaO are not well understood. An approach based on chemical reaction equations cannot capture the "CaO dissolution" process. This work presents the development of a consistent thermodynamic description of the ternary Mg-Ca-O alloy system. To that end a revision of the thermodynamic data of key oxides, CaO and MgO, has been performed based on original experimental work so far not considered in thermodynamic databases or tabulations. The formation of a liquid Mg-Ca-[O] alloy during the reaction is predicted from the thermodynamic calculations at melting temperatures; solidification simulations are also performed. These predictions from thermodynamic simulations are validated by experimental data using in situ synchrotron radiation diffraction.

Original languageEnglish
Title of host publicationMagnesium Technology 2016 - Held During TMS 2016 : 145th Annual Meeting and Exhibition
EditorsAlok Singh, Kiran Solanki, Michele Viola Manuel, Neale R. Neelameggham
Number of pages6
PublisherThe Minerals, Metals & Materials Society
Publication date2016
Pages67-72
ISBN (electronic)9781119225805
DOIs
Publication statusPublished - 2016
Externally publishedYes
Event145th Annual Meeting and Exhibition of Magnesium Technology - TMS 2016 - Nashville, United States
Duration: 14.02.201618.02.2016
Conference number: 145

    Research areas

  • CaO, In situ XRD, Magnesium alloys, Thermodynamic evaluation
  • Engineering