From a series of experiments carried out in this study, the machining characteristic of aeronautical material, titanium alloy Ti6Al4V, under dry orthogonal cutting is determined by the relations among material removal rate (MRR), tool rake angle (), and the other nine parameters in orthogonal cutting concept. Continuous and serrated chip forms are observed and chip form is determined by the flow localization parameter (). It is found that the critical values of in which serrated chip formed are ranging from = 4.71 to = 5.37 or at the chip load from 0.0045 to 0.006 mm2/min. The number of tooth (frequency) on serrated chip increases with cutting speed (V). The tool failure modes found in this study are normal flank wear, notch wear, chipping and catastrophic failure. Tool chip adhesion caused by adhesive wear mechanism and high rake angle weakened the tool cutting edge play important roles on the failure mode of the straight tungsten carbide cutting tool used in this study.