THE EFFECTS OF MACHINING CONDITIONS ON THE FLANK WEAR OF TIN-COATED HIGH-SPEED STEEL TOOL INSERTS

This paper explores the effects different machining conditions can have on the flank wear characteristics of TiN-coated high speed steel (HSS) tool inserts during dry turning. It is found that the extent of reduction in the measured wear rates depends strongly on the conditions of machining. Three major dominant wear mechanisms for TiN-coated HSS inserts have been identified; they are micro-abrasion, micro-abrasion and attrition, and edge chipping. The transition from one dominant mechanism to another is found to be more sensitive to cutting speed than to feed rate. Wear maps showing how wear rates and wear mechanisms vary with machining conditions have been constructed. They are useful in explaining some of the wear behaviour reported for TiN-coated HSS tools, and they provide an insight into how these coated tools may be better used to increase productivity.