Features of structure formation during surface quenching of cast iron with plate graphite

Abstract

The article considers the features of structure formation in the zone of the thermal impact of cast iron rolled products with lamellar graphite during surface heat treatment with a direct-acting electric arc. The process parameters affecting the phase composition and structure of the hardening zone are investigated. The dimensions and structure of the technological processing zone at different temperature characteristics of the process are determined. The processing modes that will allow obtaining of the modified structural and phase states with increased microhardness in the surface layer of cast iron under consideration are determined. The surface heat treatment of cast iron for rolls of rolling mills with plate graphite with a direct arc allows to effectively increase the hardness of the working layer with a depth of 0.5–0.7 mm due to changes in the structure in the zone of thermal impact. The characteristic features of the structural state of the surface layer of cast iron after processing are revealed.