Machinability of TIMETAL® 54M Evaluated by Milling

TIMETAL® 54M (Ti-5Al-4V-0.75Mo-0.5Fe) is an alpha-beta titanium alloy that provides a machinability benefit over Ti-6Al-4V while offering similar tensile properties.  Previous drilling and turning trials on 54M have shown improved/increased tool life at higher/high machining speeds.  A test method has been developed to evaluate machinability by end milling using a Haas vertical CNC milling machine. These test results include tool wear as a function of surface travel machined, chip characterization, and surface roughness/finish measurements. The machinability of TIMETAL® 54M has been evaluated in comparison to Ti-6Al-4V.    Evaluation of mill annealed 54M and Ti-6Al-4V with a uniform set of milling parameters shows that 54M can be machined with less damage to the tool inserts than Ti-6Al-4V.  The mechanical properties, microstructures, and surfaces of test materials are also examined.