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Title: Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs

Abstract

In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking duemore » to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.« less

Authors:
 [1];  [2];  [3]
  1. Computational Materials Laboratory, School of Engineering, Ecole Polytechnique Federale de Lausanne, Station 12, CH-1015 Lausanne (Switzerland)
  2. Calcom-ESI SA, PSE-A, CH-1015 Lausanne (Switzerland)
  3. Alcan Aluminium Valais SA, CH3960 Sierre (Switzerland)
Publication Date:
OSTI Identifier:
21056983
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729687; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; A CODES; ALUMINIUM ALLOYS; CASTING; COMPRESSION; COMPUTERIZED SIMULATION; CRACKS; CUTTING; FINITE ELEMENT METHOD; MECHANICAL PROPERTIES; OPERATION; OPTIMIZATION; PROCESSING; RESIDUAL STRESSES; ROLLING; SLABS; STRAINS; THERMAL STRESSES; THERMOMECHANICAL TREATMENTS

Citation Formats

Drezet, J.-M., Ludwig, O., and Heinrich, B.. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs. United States: N. p., 2007. Web. doi:10.1063/1.2729687.
Drezet, J.-M., Ludwig, O., & Heinrich, B.. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs. United States. doi:10.1063/1.2729687.
Drezet, J.-M., Ludwig, O., and Heinrich, B.. Sat . "Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs". United States. doi:10.1063/1.2729687.
@article{osti_21056983,
title = {Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs},
author = {Drezet, J.-M. and Ludwig, O. and Heinrich, B.},
abstractNote = {In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.},
doi = {10.1063/1.2729687},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
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