Manufacturing of polymer micro parts by ultrasonic plasticization and direct injection

In ultrasonic plasticizing, energetic ultrasound is used to heat and to plasticize thermoplastic polymers. The basic idea of the process is to deform a material cyclically at ultrasonic frequencies. The deformations are applied on the material by a common ultrasound sonotrode; the plasticization takes place in a plasticizing chamber. The generated melt is directly injected into micro cavities, and hence, micro parts can be moulded easily with the system. In this paper, micro parts being moulded with the process variation “direct injection” are analysed with regard to their weight resulting from the process parameter settings and with regard to their morphology. Furthermore, mixing effects in the plasticizing chamber are being looked at.