A wide variety of injection molding technologies is now applicable to small series and mass production

Abstract

Micro plastic parts open new fields for application, e. g., to electronics, sensor technologies, optics, and medical engineering. Before micro parts can go to mass production, there is a strong need of having the possibility for testing different designs and materials including material combinations. Hence, flexible individual technical and technological solutions for processing are necessary. To manufacture high quality micro parts, a micro injection moulding machine named formicaPlast based on a two-step plunger injection technology was developed. Resulting from its design, the residence time and the accuracy problems for managing small shot volumes with reproducible high accuracy are uncompromisingly solved. Due to their simple geometry possessing smooth transitions and non adherent inner surfaces, the plunger units allow to process "all" thermoplastics from polyolefines to high performance polymers, optical clear polymers, thermally sensitive bioresorbables, highly filled systems (the so-called powder injection molding PIM), and liquid silicon rubber (LSR, here with a special kit). The applied platform strategy in the 1K and 2K version allows integrating automation for assembling, handling and packaging. A perpendicular arrangement allows encapsulation of inserts, also partially, and integration of this machine into process chains. Considering a wide variety of different parts consisting of different materials, the high potential of the technology is demonstrated. Based on challenging industrial parts from electronic applications (2K micro MID and bump mat, where both are highly structured parts), the technological solutions are presented in more detail.

Modeling the Adhesion Bonding Strength in Injection Overmolding of Polypropylene Parts

“…The use of injection molding is even more interesting for the advantages in terms of high productivity and automatization, allowing the coupling of several technologies [ 1 ]. One of the main goals is to join two or more parts during the cycle, and for this purpose, the insert-molding or the overmolding process in its variants, from 2 K up to 4 K, is well known [ 2 , 3 ].…”