Accelerated recrystallization by electric current flash heating in cold-rolled Al-5Cu alloy under the influence of concurrent precipitation

Abstract

The influence of flash heating by using continuous direct current on the recrystallization behavior of an Al-5Cu alloy under the influence of concurrent precipitation of Al2Cu precipitates has been investigated. In comparison to isothermal annealing in salt bath, recrystallization kinetics of the Al-5Cu alloy is greatly accelerated by direct current flash heating. Full recrystallization can be achieved within a much shorter time during direct current flash heating than that by salt bath isothermal annealing. As a result, the grain structure is much finer. By excluding the heating rate effect, it is shown that the accelerated nucleation kinetics during recrystallization is due to the athermal effect of the applied current.