Machining characteristics of electroslag cast steel for hot-working tools

The machining characteristics of a tool steel manufactured by the electroslag casting process have been investigated in this study. For the evaluation of machinability, lathe turning and drilling tests were conducted. Since the chip shape characteristics reflect cutting resistance, chip shapes at different cutting speeds are examined as a means to compare the turning machinability of the tool steels. For the drilling tests, the standard deviation of drill motor current was measured by a Hall sensor and used as a measure of the drilling resistance. Machining characteristics of the tool steels are usually correlated with the mechanical properties, such as tensile strength and ductility. Turning was favoured in steels with higher tensile strength, while the opposite is true for drilling. The annealed electroslag cast steel showed good turning machinability in view of the chip shapes produced. The quenched and tempered condition had slightly better drilling machinability as compared to the annealed condition for the electroslag cast steel.