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The use of ultrasonic vibration in the manufacturing process has significant and different effects. Studying the effect of longitudinal ultrasonic vibrations on the performance of the electrical hot incremental forming (EHIF) process of Ti-6Al-4V sheets was the main purpose of this paper. In this new technique, ultrasonic vibrations with a high frequency and a low axial amplitude were combined using an electrical heater device. These devices were designed, manufactured carefully and used to perform the sheet incremental forming process at elevated temperatures. This system consisted of different parts including a mechanism attached into the chuck of the CNC machine to give the rotary motion; also, the ultrasonic power was sent to the vibratory tool. By changing some input variables including feed-rate, step-down and current, output features such as quality surface, maximum forming angle, and levels of impurities were investigated in both conventional-(EHIF) and ultrasonic-assisted-(EHIF) processes. The obtained results showed that ultrasonic assistance could increase the quality surface and decrease the impurities; also, XRD (X-ray diffraction) phase analysis showed that β phase (BCC structure) was increased due to the reduced transition, thus improving formability. |
