Design, construction, and demonstration of a novel die system for deep drawing applications with utilization of ultrasonic vibrations

This study presents design, construction, and demonstration of a patented die system (UltraDRAW) used for deep drawing applications with utilization of ultrasonic vibrations. The developed system enables application of high-frequency vibrations onto the blank holder of die system in axial direction. Such design is considered to be effective in improving drawability of blank material, resulting in drawing of blanks with greater limiting drawing ratio (LDR) and lower forming load. For this purpose, an innovative ultrasonic horn with specific geometry, used directly as blank holder, was designed with steady-state harmonic response analyses using finite element method. To evaluate the performance of developed system, a series of cup drawing experiments using conventional and ultrasonically assisted die system were performed on cold-rolled low carbon steel sheets of DC01 and DC04 under dry and lubricated surface conditions. Compared to conventional drawing, UltraDRAW improved LDR and cup depth by 9.4% and 26.5% (for DC01) and 15.1% and 43.6% (for DC04) with reduction in forming load by 22.2% (for DC01) and 18.2% (for DC04).