Rapid Solidified Al based-Alloys and Composites

F. AUDEBERT; M. GALANO; L. PERDIGUERO DIAZ; K. FUJITA; K. O`REILLY

Salvador

Congreso; RQ14 - 14th International Conference on Rapidly Quenched and Metastable Materials; 2011

One of the main current topics that materials development faces is to reduce weight, fuel consumption and pollution for engines and transport vehicles. The development of nanostructured Al-based alloys and composites is one approach to this issue. Several techniques have been used for obtaining nanostructured alloys, such as rapid solidification, spray forming, semisolid processing, severe plastic deformation and powder metallurgy techniques. Some primary techniques, like rapid solidification and gas atomization can produce very refined microstructures with high volume fractions of nanoparticles, but the materials produced are in powder, flakes or ribbon form. For industrial applications, these primary materials require to be processed into bulk forms, for instance, by means of compaction and extrusion processes. In the present work, several nanostructured Al-based alloys produced by different processing routes were studied and their structures and mechanical properties at room temperature and elevated temperatures were compared. Nanoquasicrystalline Al alloy melt-spun ribbons are compared with extruded bars produced from melt-spun ribbons, gas atomized powder and spray formed material. Moreover, these materials are also compared with hyper-eutectic Al-Si alloys produced on an industrial scale by means of extrusion of melt-spun ribbons. Mechanical properties, strengthen mechanisms and their application at elevated temperatures are discussed.