A study on the crack control of a high-speed steel roll fabricated by a centrifugal casting technique

Abstract

The effects of roll materials, mould parameter, pouring parameter and cooling parameter on the crack of a high-speed steel (HSS) roll, which is manufactured by means of centrifugal casting, are investigated. The improvement of the HSS roll is effectively achieved through the addition of suitable amounts of potassium and rare earth (RE). The hot tearing force (i.e. the resistance to hot tearing) of the modified HSS roll is increased by 32.77% and reaches 158 N, while the line constriction (i.e. the solidification constriction of the HSS in unit distance) is decreased. In addition, the temperature field and stress field of the roll can be improved by adopting variable-speed centrifugal casting, variable-flux pouring and variable-speed solidification cooling techniques, which help to improve the filling and solidification of the molten steel and eliminate the cracks.