On wear of WC–Co cutting inserts in turning of Ti6Al4V – a study of wear surfaces

ABSTRACT Titanium alloys are known to cause crater wear on cutting inserts. It is one of the life-limiting factors for the tool life and highly influenced by the cutting parameters. To increase productivity, there is a strong incentive to increase the production speed. At the same time, the tool life should be unchanged or even prolonged. The influence of cutting speed, feed and cutting length on wear was investigated in turning tests using cemented carbide inserts and titanium alloy Ti6Al4V as work material. The results showed a very strong influence from all parameters on crater wear, confirming previous findings reported in the literature. The resulting wear surfaces were studied in detail, revealing a crater filled with transferred titanium alloy. The tungsten carbide grains underneath were depleted of carbon, resulting in a nano-rough top surface rich in tungsten. In addition, the turning tests showed a threshold cutting speed, below which no crater wear occurred.