Investigating and modeling tool-wear rate in the ultrasonic machining of titanium

Titanium is known as the metal of the future because of its excellent combination of properties such as high specific strength, low thermal conductivity, and high corrosion resistance. There is a critical need for developing and establishing cost-effective methods for the machining of titanium, especially in terms of tool-wear optimization. This paper addresses the application of ultrasonic machining, an impact machining process for the cost-effective machining of commercially pure titanium (ASTM Grade-I) and evaluation of tool-wear rate under the effect of different process parameters. Tool material, abrasive material, slurry concentration, abrasive grit size, and power rating of the ultrasonic machine were included as the input factors in this investigation. The optimal settings of these parameters were determined through experiments planned, conducted, and analyzed using the Taguchi method. The significant parameters contributing most to the variation in tool-wear rate were identified and the results obtained were validated by conducting the confirmation experiments. Thereafter, the outcome of the Taguchi model has been used for developing a micro-model for tool-wear rate (TWR); using Buckingham's pie theorem. A comparison of the experimental results obtained assists in the validation of the model.