High impact load during the tool engagement with workpiece during entry and exit creates to tool crack and failure.
- Variation in cutting speed has a predominant influence of tool life, regardless of whether there is variation in either feed rate or depth of cut.
- Coated tool produces better surface finish at higher cutting speeds, but the tool wear rate is very rapid. Dom inant tool wear is at flank face and the abrasion is the wear type.
- Uncoated inserts performs better at moderate rate cutting speeds comparing to coated inserts, but at higher cutting speeds the tool experienced maximum flank wear. The frequency of intermittent cut increases as the cutting speed increases which is the major reason for this