The analysis of the microstructure, mechanical properties and distribution of elements across the interface of ductile iron and stainless steel allowed us to propose the following conclusions:
Friction welding is accompanied by a transport of atoms in both directions across the ductile iron-stainless steel interface. This results in the enrichment of stainless steel with carbon, and ductile iron with chromium and nickel atoms. Stainless steel carbon enrichment results in the formation of chromium carbides that are distributed mostly at the grain boundaries. Iron enrichment in Cr and Ni resulted in the creation of an alloy ferrite. Cr was found also in a carbide eutectic.
The range of Cr and Ni diffusion in iron generally does not exceed 50 m. The depth of the diffusion of carbon in the case of a joint subjected to a double thermal effect is 150 m and higher than for a sample subjected to one step friction welding.
The intensity of diffusion processes during friction welding of bainitic ductile iron is larger than for ferritic ductile iron.