Structure and phase composition of diffusion zones formed as a result of homogeneous and heterogeneous reactions at the boundary of the AD1-Cr15Ni60 composite

Abstract

Abstract This paper presents the study results of the diffusion interaction processes at the interlayer boundary of explosion welded Cr15Ni60-AD1 bimetal during the occurrence of homogeneous (at the solid – solid interface) and heterogeneous (at the solid – melt interface) reactions. It was shown that the diffusion zone formed during homogeneous interaction has a layered finely dispersed structure, while in a heterogeneous one it is predominantly needle-shaped with large fragments of the structure. Diffusion zones are characterized by heterogeneity in chemical composition, while their phase composition is almost identical: CrAl7, FeNiAl9, (Fe,Ni,Cr)Al9, (Fe,Ni,Cr)Al5, NiAl3, (Ni,Fe,Cr)Al. It has been established that the transition from the interaction at the solid – solid interface to the interaction at the solid – melt interface leads to a significant acceleration of diffusion processes.