Temperature reduction in the cutting zone in water-jet assisted turning

The life of a cutting tool, and the efficiency in metal cutting, is mainly dependent on the heat that is generated in the contact zone between the tool rake and the machined material. Conventional or low-pressure cooling methods are not sufficiently efficient to penetrate the zone and change the thermal, frictional and mechanical conditions in the cutting zone. The effects of a high- and ultra-high-pressure water jet directed into the tool/chip interface on tool temperature, cutting forces, chip shape and surface roughness in regular turning operations have been explored in this investigation. For evaluation of the cooling effects special inserts with integrated thermocouples were used. The results show that a significant reduction of edge temperature, by 40-45%, is possible. This is achieved by using jet pressures in the range 40-300 MPa. Measurements of temperatures and forces were made for different cutting conditions, such as cutting speeds and feeds, and different fluid parameters, such as pressures and volumes. (C) 2000 Elsevier Science B.V. All rights reserved.