Experimental Study on High Speed Milling of γ-TiAl Alloy

This paper deals with the milling machinability of gamma titanium aluminide at speeds of 60-240m/min. The results showed that surface roughness was less than Ra0.44μm at all cutting speeds used in the tests even when the tool wear reached VB0.2mm. The milling forces increased slightly with increasing cutting speed but increased rapidly with the elevated flank wear value especially for the Fy component. Compared to those of titanium alloy TA15, the milling forces of γ-TiAl were 190%, 180% and 200% greater for Fx, Fy and Fz respectively under the same machining conditions. Workpiece surface has a maximum microhardness of approximately 600HV0.100, and the depth of maximum hardened layer was confined to 180μm below the surface. When cut with TiAlN coated carbide tool, tool life was 35 min which was only about 1/2 of that for titanium alloy TA15.