Research on the Bimetallic Composite Roll Produced by an Improved Electroslag Cladding Method: Mathematical Simulation of the Power Supply Circuits

Bimetallic composite roll has been given more and more attentions because of its superiority in playing the advantages performance of the internal and external materials at the same time. In the present study, a 2D quasi-steady state mathematical model of the electroslag cladding technology for producing bimetallic composite roll was developed by the Fluent software with the UDS and UDF function. Characteristics of the electromagnetic field, flow field and temperature field of the composite roll system have been numerically simulated and the laboratory scale experiments with the different power supply circuits were also developed to provide a verification of the mathematical models. The results indicate that: simulation results of the temperature distribution in the composite roll were well verified by the corresponding experiments. With the using of current supplying mold (CSM), the improved conductive circuit is more beneficial to improve the distributions of current density and Joule heat in the slag pool and keep the high temperature zone away from the roll core surface than the conventional conductive circuit. On one hand, it makes the roll core be no longer as a pole of the electroslag process and the temperature adjustment of the slag pool become more flexible. On the other hand, it leads to a partial micro-melting of the roll core surface which is beneficial to form a metallurgical bonding and effectively avoid the mechanical mixing of the liquid metal between the roll core and composite layer, so, it can improve the comprehensive performance of bimetallic composite roll.