di Gianluca Cicala, Giuseppe Abramo, Davide Giordano, Roberto Catenaro
University of Catania and ACS (Advanced Composites Solutions) company jointly invested in the development of additive manufacturing techniques to make complex composite parts. The use of the professional FDM machine Fortus 400mc, made available in the research group of professor Cicala, was at the basis of the industrial research.
Additive manufacturing, also called 3D printing, allows to create complex shapes and can be used for the manufacture of complex tooling to replace expensive tools made by subtractive technologies.
With this principle in mind the researcher worked on the development of complex mandrels (fig.1 and fig.2) made off polymers soluble in water based solutions.
Some of the work was focused also on structural parts (fig.3) in which the high temperature and mechanical resistance was ensured by the use of an advanced techno-polymer like Ultem 9085. In the latter case, to ensure lightness the core of the part was made with an hexagonal structures, similar to standard sandwich core materials, which conformed all the shape (fig.4).
Different internal architectures for the soluble mandrels were tested in order to optimize the dissolution phase while ensuring good surface finish and high thermomechanical resistance to withstand the production both in the autoclave and with out of autoclave techniques (fig.5).
The mandrel in Ultem 9085 was covered with pre-preg for out of autoclave moulding from Cytec Engineered Materials (VT-261) and processed under vacuum only. The use of FDM core materials in Ultem allowed to realize a light support bracket (550 grams) to hold a BLDC motor (Fig.4). This bracket is intended for use in an electrical vehicle.
12 April 2017