The Tool Restricted Contact Effect as a Major Influencing Factor in Chip Breaking: An Experimental Analysis

Summary: Chip breaking performances of six commercially available chip forming tool inserts have been assessed. The tool restricted contact effect determining the chip streaming (i.e. chip backflow) has been found to be a major influencing factor in chip breaking. No commercial chip former fully utilises the restricted contact effect. Chip up and side curling mechanisms have been investigated. Deforming the chip laterally across the chip-section contributes to the chip breaking. Commercial chip formers have been found to lie in an intermediary level between flat-faced conventional tools and restricted contact tools in terms of cutting power consumed.