Experimental and numerical study of ultrasonically-assisted drilling.

In this study, 3D finite element simulation of ultrasonically-assisted drilling is carried out to analyze the effect of ultrasonic vibrations on common difficulties existed in conventional drilling. Influence of harmonic movement of drill bit on the formation of built-up edge is experimentally evaluated and also discussed by investigation of heat generation on the tool faces in simulation. At the end, it was revealed that intermittent movement of drill bit in vibration method causes the total time of heat transfer between workpiece and drill bit to be reduced resulting lower built-up edge formation compared to conventional drilling. Moreover, linear motion of cutting tool in the feed direction results in the increase of chip strain and consequently damage value which causes to generation of broken chips.