In machining technology, increasing tool life is crucial for reducing manufacturing costs. One possible method to extend tool life is cryogenic heat treatment, which can improve the wear resistance of cutting tools. This publication investigates the effect of soaking time in liquid nitrogen (8, 16, and 24 hours) and tempering temperature (200 and 550 °C) on the hardness and run-out of the tool material. The highest hardness (716.12 HV) and lowest run-out (6.606 µm) were measured in the tool blank soaked for 24 hours and then tempered at 550 °C. Therefore, tools manufactured from this heat-treated material were used for the machining tests. During the machining tests, tools were compared under identical cutting times and varying cutting speeds (20, 25, and 30 m/min) in face milling operations with emulsion cooling. The comparison focused on the Fxy resultant cutting force and flank wear measured using untreated and cryogenically treated tools. At a cutting speed of 30 m/min, the cryogenically treated tool experienced catastrophic wear. At a cutting speed of 25 m/min, the cryogenically treated tool achieved nearly 10% lower flank wear and almost 50% lower resultant cutting force (Fxy) compared to the untreated tool.
Science Journal 