EMPACT: A European program on aluminium casting technology. Development of predictive tools for aluminium ingot casting performance.

• Research unit: EU RFP
• Project number: 95.0037-3

Key words (English)

DC-casting; FEM simulation; fluid flow; experimental casting measurements; heat transfer; crack; segregation

Alternative project number (English)

EU project number: BRPR-CT95-0112

Research programs (English)

EU-programme: 4. Frame Research Programme - 2.1 Industrial and materials technologies

Short description (English)

See abstract

Partners and International Organizations (English)

Hoogovens R&D, Hydro Aluminium a.s. Metallurgical R&D Centre, Elkem a/s Research, Pechiney CRV, VAW aluminium AG R&D, Calcom S.A., Technische Universiteit Delft, INP-Lorraine/Ecole des Mines de Nancy, Ecole Polytechnique Federale de Lausanne

Abstract (English)

Task 1:
Sub-task 1.1: IFF Tests
Coupled fluid flow-thermal-structural calculations for the 2d numerical simulation of the direct-chill ingot casting process:
Demonstration of a new method and sensitivity study on the influences of fluid flow variations

Alusuisse investigated the influence of the metal motion on the thermal and consequently on the stress-strain fields in the ingot, for the numerical simulation of the direct-chill ingot casting process. Coupled fluid flow - thermal - structural 2d calculations were performed according to a new model, using the ANSYS Multiphysics code which allows one to couple the fluid flow to the thermal phenomena as well as to calculate the transient structural behaviour of the ingot from the temperature distribution. Thermal boundary conditions and physical properties of the modelled AA1xxx aluminium alloy were similar as those defined in the Task 1 report of July 1996.
Temperature fields inside the ingot and the associated rolling face pull-in (i.e. the thermal contraction) were calculated using visco-elasto-plastic modelling, from the beginning of the drop to the very end of ingot cooling.
The influences of fluid flow variations at the combo-bag location were studied under various horizontal and vertical speed conditions (1. Horizontal speed 5 mm/s; bag height = 50 mm. 2. Horizontal speed 10 mm/s; bag height = 25 mm. 3. Vertical speed 5 mm/s; bag height = 50 mm. 4. No fluid flow).
Temperature fields, fluid motion, displacements of the ingot faces and stress/strain distributions were calculated.
The influence of fluid flow on the solidification of the ingot is highlighted. The results of the calculations show modifications in the sump shape and depth due to changes in the velocity distributions, as well as changes in the stress and strain distributions and in the displacements in horizontal and vertical directions.

Most of these results were presented at the Empact biannual meeting (July 7 1999) and written into a report, and presented at the Task 1 meeting at VAW Bonn (November 4 1999) . An abstract (same title) has been submitted and accepted at the Modelling of Casting, Welding and Advanced Solidification Processes IX (MCWASP IX) 'SIM 2000' 20-25 August 2000, Aachen, Germany. The paper will be submitted in January/February 2000.



Task 6:
Sub-task 6.2: Macro-segregation measurement and grain structure analysis.

Selected slices from AA6063 slab previously cast at Chippis were cut into 50x50 mm samples according to a predefined plan. These samples were analysed with the OES for macro-segregation mapping. The results of measurements have been forwarded to Ecole de Mines at Nancy (EMN). Samples from the slices were prepared for macroscopic examination (grain size evaluation). EMN is expected to specify the part of interest for further analysis.
Another slice from the slab was sent to Technical University Delft for thermo-mechanical analysis of AA6063 material in the as-cast condition.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 95.0037-3