Tool wear and tool life in end milling of 15-5 PH stainless steel under different cooling and lubrication conditions

Most of the machining operations on stainless steel alloys are carried out with cutting fluid due to the poor machinability of this kind of material. Tool wear mechanisms are directly influenced by the cooling and lubrication condition to which the tool is exposed, especially in interrupted cutting processes. This work investigates tool wear mechanisms for an end milling operation of a precipitation-hardened martensitic stainless steel under four different cooling and lubrication conditions. The results demonstrated that the cooling and lubrication condition strongly influences tool life and the tool wear mechanism, and furthermore, that tool lubrication rather than cooling should be the purpose for using cutting fluid in this kind of operation, in order to avoid damage caused by tool temperature variations.