Investigation on PCD cutting edge geometry for Ti6Al4V high-feed milling

Abstract

Some new research challenges are connected to new high-feed milling tools, developed recently to reduce the cutting time. The main objective of this article is to analyze if PCD tools could be used for high-feed face milling of Ti6Al4V. As its performance depends significantly on cutting edge geometry, different tool geometries were evaluated regarding tool life and cutting forces. Experimental investigations demonstrate that the tool profile, which has a discontinuity on chip flow direction along the cutting edge, presents an intense local tool wear and, consequently, a smaller tool life. The PCD tool having a straight edge has a longer tool life but, contrarily to the carbide tool theory, local wear behavior on the cutting edge is not constant when depth of cut increases. The cutting force magnitude, and its dynamic, affects drastically the tool life of PCD tools in milling and it is a limitation to the increase of the material removal rate. In conclusion, it is possible to use specific PCD tools for milling titanium alloy in high feed with low depth of cut (smaller than 1 mm), which is not economically practicable.