EFFECT OF PRECIPITATION ON THE EVOLUTION OF CUBE RECRYSTALLIZATION TEXTURE

A study of the evolution of recrystallised structure and texture in th e surface of a cold rolled twin roll cast AlFeSi alloy is presented. A nnealing of such alloys often results in an abnormally coarse grained recrystallised surface structure with a strong cube texture. The evolu tion of this structure depends on the annealing procedures, that is, t he precipitation state. Increased amounts of precipitating particles i ncrease the grain size and the fraction of cube texture. The oriented growth theory does not offer any plausible interpretation of this prec ipitation effect. A recrystallisation model that incorporates the diff erences in Zener drag between different annealing procedures has shown that the evolution of a strong cube texture and coarse grains is the result of a preferential nucleation of cube oriented grains. Precipita tion increases the critical nucleation diameter and the resulting grai n size. Cube oriented subgrains have a size advantage compared to othe r potential nucleation sites and are therefore not so affected by prec ipitation. (C) 1997 Acta Metallurgica Inc.