Effect of cutting fluid on surface roughness in ultra-precision cutting of titanium alloys

This report aims to investigate experimentally the effect of cutting fluid on the surface roughness in the ultra-precision face-turning of titanium alloys. The experiments are executed in face-turning by a single crystal diamond bite and a coated cemented carbide bite set on the ultra-precision lathe. The face-turned titanium alloys surfaces are examined by observing with a Nomarski differential interference microscope and measuring with WYKO and SEM. The coated cemented carbide bite is much more suitable for ultra-precision cutting of pure titanium and titanium alloys than a single crystal diamond bite. In the case of the coated cemented bite, surface roughness below 100 nm (P-V) is kept beyond cutting length of 2,000 m while the surface roughness in a diamond bite becomes about 300 nm (P-V) at the cutting length about 80 m.