Kinetics of Phase Transformations in FeAl(Cr,Si) / Fe₃Al(Cr,Si) / Fe(Al,Cr,Si) Laminated Coating on the Cr15Al5 Alloy

Abstract

The influence of thermal action at 1150 °C on the kinetics of phase transformations in a layered coating FeAl (Cr,Si) / Fe3Al (Cr,Si) / Fe (Al,Cr,Si), obtained using a technology involving aluminizing of an Cr15Al5 alloy by hot dipping in silumin melt AK12M2 and heat treatment. It was shown that after 100 hours of exposure, the visually distinguishable boundary between the coating and the alloy disappears. The aluminum content in the Cr15Al5 alloy increased to 17 at. %, silicon up to 3 at. %, and chromium is reduced to 14 at. %. The microhardness of the alloy increases from 1.6 to 2.4 GPa and survivability at a test temperature of 1150 °C increases from 120 to at least 920 hours.