Cryogenic machining as an alternative turning process of normalized and hardened AISI 52100 bearing steel

Environmental and health friendly technologies with economic justification have nowadays an increasing importance in global industrial trends. Idea of global sustainable development dictates cleaner and less health hazardous machining processes. With these limitations in mind, the main issue is now to change the way mechanical components are being machined and move to alternative technologies that could moreover increase the machining performance. Cryogenic machining is one possibility to reach this goal. It consists of a system for cutting (turning, milling, etc.) assisted by liquid nitrogen, which enables a clean process with possible lower production costs and higher productivity. This article presents the results of turning hardened and normalized bearing steel AISI 52100 (DIN 100Cr6), comparing conventional flood and dry with cryogenic machining. Turning results show drastic improvements in tool lifetime (up to 370%) for cryogenic machining of normalized bearing steel 100Cr6 and reduction of thermal residual stress inducements in case of hardened bearing steel 100Cr6, while tool life is also extended.