Extrusion Modelling of Aluminum Particulate Composites

摘要

Particulate Al matrix composites inexpensively fabricated into large billets by liquid metal mixing receive final fabrication into components by mechanical forming, notably at high temperatures to minimize cracking and particle-matrix degradation. A hot torsion project on alloys 6061, A356, 7075 and 2618 with 10 to 20 percent of Al_2O_3 or SiC determined hot strength and ductility, constitutive constants and microstructural evolution. The substructure is very heterogeneous exhibiting regions of subgrains, non-cellular masses of dislocations and small highly misoriented cells. The modeling of extrusion of the various particulate metal matrix composites was conducted by finite element analysis to develop strain rate, mean stress and temperature distributions. The relative load-stroke curves and extrudability were compared.