MICROSTRUCTURE AND KINETICS OF RECRYSTALLIZATION OF HOT DEFORMED AL-AL2O3 PARTICULATE-REINFORCED METAL-MATRIX COMPOSITE

A particulate metal matrix composite consisting of a 2000 series matri x reinforced with 20 vol.-% alumina particles was annealed at 500 degr ees C following hot working over a range of deformation conditions. Th e kinetics of recrystallisation and microstructural behaviour during h eat treatment were determined by optical and transmission electron mic roscopy. The behaviour of the composite was compared with that of the unreinforced matrix alloy processed under the same conditions. Static recrystallisation during post-hot working heat treatment occurred over a slightly wider range of prior deformation conditions in the composi te, and yielded finer recrystallised grains compared with the alloy. T his behaviour was attributed to the greater deformation heterogeneitie s in the as hot deformed composites compared with the unreinforced all oy. (C) 1995 The Institute of Materials.