Hot cracking; wrought aluminium alloys; thixoforging; LiMaRC - Liège Materials Research Center
Abstract :
[en] Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7<fs<1), which involves the processing of alloys in the semi-solid state. The use of semi-solid material with globular microstructure helps to decrease forming load. But the introduction of a liquid phase in the material is a source of defects that limit mechanical properties of thixoforged parts. One of these defects is the hot cracking for some hot crack-sensitive wrought aluminium alloys. Hot cracking occurs because of strain and deformation during last step of solidification. This paper shows how thixoforging process helps to lower hot cracking tendency without modification of the alloy composition by decreasing strain and deformation due to shrinkage. Different experimental tests by extrusion of 7075 aluminium alloys are used.
Disciplines :
Materials science & engineering
Author, co-author :
Vaneetveld, Grégory ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Rassili, Ahmed ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Pierret, Jean-Christophe ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Lecomte-Beckers, Jacqueline ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Science des matériaux métalliques
Language :
English
Title :
Benefits of thixoforging hot-crack-sensitive aluminium alloys at high solid fraction
Alternative titles :
[fr] Avantages du thixoforgeage à haute fraction solide des alliages d'aluminiums sensibles à la fisuration à chaud
M. C. Flemings: Metall. Trans. A Vol. 22A, pp. 957-981, 1991.
Metals Handbook®, Desk Ed., ASM, Ohio, 1984.
G. Vaneetveld, A. Rassili, J. Lecomte-Beckers, H. V. Atkinson, Thixoforging of 7075 aluminium alloys at high solid fraction, Solid State Phenomena Vols. 116-117, pp. 762-765, 2006.
M. G. Chu, D. A. Granger, The Tensile Behaviour and Cracking Tendency of Partially Solidified Aluminium Alloys, Proc. Of the 4th Decennial Intern. Conf. on Solidification Processing, University of Sheffield, United Kingdom, pp. 198-202, 1997.
D. G. Eskin, Suyitno, L. Katgerman, Mechanical properties in the semi-solid state and hot-tearing of aluminium alloys, Progress in Materials Science, 49, pp. 629-711, 2004.
G. Vaneetveld, A. Rassili, J. C. Pierret, J. Lecomte-Beckers, Improvement in thixoforging of 7075 aluminium alloys at high solid fraction, Solid State Phenomena, Trans Tech Publications, 141-143 Switzerland, pp. 707-712, 2008.
G. Vaneetveld, A. Rassili, J. C. Pierret, J. Lecomte-Beckers, Extrusion tests of 7075 aluminium alloy at high solid fraction, Int J Mater Form, Suppl 1, pp. 1019-1022, 2008.
G. Vaneetveld, A. Rassili, J. C. Pierret, J. Lecomte-Beckers, Influence of parameters during induction heatingcycle of 7075 aluminium alloy with RAP process, Solid State Phenomena, Trans. Tech Publications, 141-143, Switzerland, pp. 719-724, 2008.
C. Rouff, Contribution à la caractérisation et à la modélisation du comportement d'un acier à l'état semi-solide, Application au thixoforgeage, Thèse, France, 2003.
G. Vaneetveld, A. Rassili, J. C. Pierret, J. Lecomte-Beckers, Conception of tooling adapted to the thixoforging of high solid fraction hot-cracksensitive aluminium alloys, submitted to S2P 2010 Conference.
