INFLUENCE OF AXIAL FEED IN HOBBING WITH MINIMAL QUANTITY LUBRICATION (MQL) ON WEAR OF THE HOB AND CUTTING FORCES

In the paper evaluation of the influence of axial feed on the hob wear in hobbing with minimal quantity lubrication technique has been done. As a work material C45 carbon steel has been investigated. Wear resistance of the hob made from high speed steel HS6-5-2 without coating has been investigated. For comparison tests with conventional fluid supply method have been carried out. Gears have been generated with full depth of cut and with two axial feed with constant cutting speed value. During hobbing cutting forces have been measured by experimental stand. Tool wear has been measured directly as a width of flank wear land of the hob cutter teeth. During investigation any significant wear changes on the rake faces haven't been detected, so those results haven't been taken into consideration. A constant length of cut parameter has been established as a criteria value. Results of investigation have been presented in the form of graphs describing changes of wear land width parameter in comparison to the most loaded tooth wear land parameter. Also changes of cutting forces in time are presented too. On the base of obtained results conclusion has been formulated that MQL technique might be used as an alternative solution for supplying cutting fluid into the cutting zone during hobbing process.