Research on the bimetallic composite roll produced by a new electroslag cladding method: microstructure and property of the bonding interface

According to the previous numerical simulation, a bimetallic composite billet has been produced by the new electroslag cladding method in the present study. Its longitudinal and circumferential macrostructure analyses clearly illustrates that the bonding trend of bimetallic metals changes from slag inclusion defect to good metallurgical bonding with the increasing composite height, which is closely related to the temperature distribution in bimetallic interface. Tensile strength of as-cast sample including the bonding interface can reach 661 MPa with a good plasticity and toughness. In addition, tensile fractures of the as-cast and annealing samples are always located on the roll core side rather than the bimetallic bonding interface which fully prove that the bonding interface is not the weakest area of the composite billet. Based on the above analyses, some useful suggestions about improving the composite billet quality produced by the new electroslag cladding technology have been given.