An experimental investigation of temperature and machinability in turning of compacted graphite irons

The life and the performance of an insert in metal cutting are mainly dependent on the heat that is generated in the contact zones on the tool rake face with chips and on the flank face with the transient and machined surfaces. According to tool life standard, the wear on the flank face is usually taken as a decision for tool life. This occurs because of contact stresses, temperature and friction between tool workpiece contacts. Hence, knowledge of temperature on the flank face becomes important. The temperature on the flank face has been measured in this work for different CGI materials having different microstructure and physical properties in a turning operation. It has been seen that there is no significant difference of flank temperature, while machining different CGI materials having hardness from (140 to 236 HBW). For temperature measurement, special inserts integrated with gold-platinum thermocouple on the flank face were used. It has been noticed that the materials having 31% resultant cutting force difference and six to eight times tool life difference have almost same temperature on the flank face measured at different distances from the edge line of the insert.