Advances in the Turning of Titanium Alloys with Carbide and Superabrasive Cutting Tools
Machining efficiency of titanium alloys is crucial to the aerospace industry especially in the manufacture of bladed discs (blisks) where over 80% of titanium alloy material is roughed out to generate the complex shapes and contours of components. The choice of the right tool materials for machining titanium alloys contributes enormously to reducing the overall machining time by significantly lowering the cycle time and indexing of the cutting edges. These improvements lead to a reduction of the manufacturing cost by up to 30%. Uncoated and coated carbide tools have demonstrated encouraging performances when turning Ti-6Al-4V alloy, especially under roughing operations complemented by high pressure cooling technology, at high cutting speed and depth of cut conditions that increase the metal removal rate. Under such cutting conditions there is no significant difference in performance between coated or uncoated carbide tools when turning Ti-6Al-4V alloy. Super abrasives like ceramics and cubic boron nitride (CBN) tools are not suitable for machining titanium alloys as low tool life with no economic benefit is achieved because of severe chipping and fracture of the cutting edge. Machined surfaces produced with ceramic tools have very low surface integrity status because of loss of form as a result of accelerated tool wear and the consequent chipping and fracture encountered during machining. Polycrystalline diamond (PCD) tools are suitable for finish turning Ti-6Al-4V alloy at cutting speeds up to 250 m/min.
Prof. José Divo Bressan, Prof. Maurício Vicente Donadon
R. B. da Silva et al., "Advances in the Turning of Titanium Alloys with Carbide and Superabrasive Cutting Tools", Advanced Materials Research, Vol. 1135, pp. 234-254, 2016