COST 507 - Repositório Aberto da Universidade do Porto

A Thermochemical Assessment of Data for the Al-rich Corner
of the Al-Fe-Mn System, and a Revision of Data for
the Al-Mn System
Abstract
Åke Jansson' and Tim G Chart*
"Royal Institute of Technology, Stockholm, Sweden
*Chart Associates, Ashford, Middlesex, UK
This research forms part of the COST 507 programme on the Al-Fe-Mg-Mn-Si system
(Leading System 1). It includes a revision of data for the binary Al-Mn system, based
upon the original COST 507 assessment for this system [92Jan, 94Ans] and an
optimisation of data for the Al-rich corner of the Al-Fe-Mn ternary system, which in
addition to the available published data, incorporates the results of experimental
measurements carried out during the Action by a combination of Alean International
Ltd (Banbury Laboratory), Katholieke Universiteit Leuven, Pechiney, SINTEF,
Universität Wien and University of Manchester/UMIST; these experiments specifically
performed to provide missing data, as described in other papers of the proceedings of
the COST 507 Final Workshop, eg [97Rob/Hay].
The overall system currently under study is the Al-Fe-Mg-Mn-Si system. The phase
relationships in the base Al-Fe-Mn-Si system itself are very complex and not wellestablished.
In particular, during Leading System 1 meetings held on the quinary
system and its constituent sub-systems, it became clear that the phase diagram data for
some of these key sub-systems, largely based on the early work of Phillips [43Phi]
may be subject to considerable experimental uncertainty, especially data for the Al-Mn
binary system and the Al-Fe-Mn and Al-Mn-Si ternary systems, due, eg, to difficulties
of nucleation, the presence of metastable phases and the effects of impurities.
The results of the assessments are summarised. The experimental phase equilibrium
studies carried out in combination by the above groups have proven to be essential to
the project. It is clear, however, that some further careful experimentation is required.
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