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
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