Ultrasonic Orbital Microforming—A New Possibility in the Forming of Microparts

Abstract

The demand for very small metal parts is growing rapidly due to the development of micromechanisms. In microtechnology, the dimensions of scale parts are below 1 + c mm, where c varies based on the process type. The “classic” processes usually cannot be simply scaled down, and tools require thorough structural changes. Microforming has been isolated from the area of “classic” metal forming and is governed by modified laws. The proposed new technological process ultrasonic orbital microforming (UOM) and its related phenomena are possible only on a microscale. UOM is a process that uses the broadly understood idea of orbital forging, which involves rolling on a closed road. This, however, is where the analogy ends. The UOM process uses completely different laws of physics. The process, the result of which is the axial-symmetrical micropart, consists of inducing a fast rotational movement of the billet by a punch that is vibrating at an ultrasonic frequency. The rotational speed is so fast that gyroscopic effect plays an important role. This work presents the concept of the process, preliminary research results, and their general interpretation. FEM-3d modeling of micro-orbital forming processes in geometrically similar conditions to the UOM process was also performed, obtaining shapes consistent with those obtained in the UOM.