Precipitation in iron–chromium–aluminium alloys

Abstract

Small angle neutron scattering was used to study the precipitation in two iron–chromium–aluminium alloys of similar composition, the main difference being the addition of yttrium to one alloy. The mean diameter, separation, and volume fraction of the precipitates is determined as a function of aging time and temperature. The two alloys behaved differently, the precipitate growing more quickly in the yttrium containing alloy. The upper limit of stability of the chromium rich phase was established as lying between 480 and 485°C in both alloys.