Cast steel products, ferrous and non-ferrous [mandrel segment]

Heat-resistant crack-resistant segments for hot-rolled winding.

Traditionally, segments for hot rolling were made from low-alloy cast steel products of Cr-Mo or Mn-Cr systems, or high-temperature and high-pressure cast steel products of the Cr-Mo system. However, these materials were discarded due to friction, deformation, and surface heat cracks, with heat cracks generated by heating and cooling being a major cause of reduced lifespan. Therefore, materials with excellent heat crack resistance were required. By increasing the carbon content in steel, hardenability can be improved, and wear resistance and deformation resistance can be addressed through tempering adjustments. However, increasing the carbon content also decreases heat crack resistance and impact values, so materials with higher carbon content do not yield good results under the harsh operating conditions of segments. Our developed YST-5 minimizes the carbon content necessary to improve heat crack resistance, adding special elements to a composition of 1.3% Cr and 1.0% Mo, and applying special heat treatment. As a result, it maintains the mechanical properties required for segments, exhibits excellent heat crack resistance, has no temper brittleness, and retains temper resistance, making it the optimal material for the harsh operating conditions of segments.

Processing Contract