A comprehensive machinability comparison during milling of AISI 52100 steel under dry and cryogenic cutting conditions

Abstract

Fabrication of complex and flat shapes is usually processed by milling operation with multi-point cutting tools. In this research, the potential of cryogenic and dry milling was investigated under varying cutting speed (50–250 m/min) and the feed (0.05–0.15 mm/tooth), while machining of AISI 52100 steel at a constant depth of cut. PVD TiAlN coated carbide cutting tool was employed in this research. The results show a reduction of 52%–78% in the white layer (WL) thickness under cryogenic cooling (LN2) environment due to its high thermal cooling effect. A drop out of 49% in the cutting temperature has also been observed if LN2 cooling is used instead of dry milling. Cryogenic cooling provides a 28%, 28%, and 29% decrease in the cutting forces; FX, FY, and FZ, in comparison with the dry milling. Furthermore, the roughness of the machined specimen reduces by 29% if the LN2 cooling mechanism is engaged in milling of AISI 52100. Study of chips morphology revealed that the cryogenic LN2 machining produced discontinuous, thin and small serrated chips with silver color.

Effect of edge radius on forces, tool wear and surface integrity under edge radius dominated tool-chip contact conditions

“…This induces strain-hardening phenomenon in the machined subsurface leading to increase in micro-hardness. 43 This can also be correlated to the broadened XRD peak of the machined surface obtained for larger edge radius (65 µm) tool.…”