Investigation of the Diffusion Zone Formation Mechanisms during the Production of Functional Steel-Aluminium Compositions by Arc Processes

Interaction at the interface during the production of functional steel-aluminum compositions by arc processes has been investigated. Regularities and mechanisms of the diffusion zone formation have been proposed upon contact of a melt based on aluminum, alloyed with 11-13 wt% Si, with the steel substrate or Al-Fe system intermetallic compounds. It was found that the presence of Si in the composition of filler material leads to diffusion mobility of Al and Fe decreasing due to the replacement of Al, as well as the occupation of structural vacancies in double FexAly intermetallics and ternary intermetallic phases with different stoichiometric composition FexAlySiz formation. It was determined that during the arc cladding process using as substrate the steel with intermediate zinc coating, a diffusion zone with an average thickness of 7 μm is formed, while in the presence of an intermediate coating from aluminum deposited by the “cold metal transfer” process, its average thickness is 18 μm.