Polyjet Prototype and final electrode made up by electroforming
The UV photopolymerization technology, also known as Polyjet or 3D impression, allows the manufacturing of pieces with a high dimensional accuracy, subtle details and smooth surfaces. The last developments have made possible the production, through these technologies, using two different materials and even to generate digital materials as a composition of the two base materials.
For these processes, AIJU uses Objet Connex 350, able to build final products up to 350x330x200 mm and final products with good final characteristics and similar behaviour to silicone or rubber. Their applications include, among others, the manufacturing of prototypes for benchmarking actions or the production of masters for vacuum casting moulds, moulds of wax injection to use in the lost wax technology or even high precision and detailed female electrodes, which are the most economical methodology for short production series.
Cesar Carrión, responsible for the Product Development Area at AIJU’s Product Development -Laboratory Department, says: “Thanks to the multiple variety of properties that digital materials that can be generated by the Polyjet Matrix technology present, a stiff objet with flexible buttons in the same piece seamless and without fissures or cracks can be created, for instance. This technology has also entered the customization market through specific machines for the headphone manufacturing. Its acrylic resins are homologated for uses in the health industry; one of the clearest application fields is the manufacturing of surgical splints used in non-invasive dental prosthetic surgery”.
Selective Laser Sintering (SLS) is a less accurate technology that requires the laser beam recalibration or re-adjustment system employing scale factors on the pieces to be manufactured as, otherwise, it provides a deviation regarding the original design. The scale used in SLS is very large and can show large differences in its values.
AIJU has used the scaling values of the SLS technology in order to provide a smaller scale applicable to Polyjet technology. Therefore, in the study, AIJU has achieved an accuracy 10 times the initial value calculated with no scales. Thus, Polyjet technology has become even more accurate and, optimized, can achieve exceptional accuracy values.
Cesar Carrión establishes that “other studies have been undertaken regarding the scaling of the Objet Technology. Nevertheless, the proposed model in this study is very complex and the correct scale factor is, in our opinion, as important or even more as the CAD model to be compared as well as all the possibilities in dimension marking. That is why, although the technology manufacturer tells us that it is not necessary to carry out this process, exceptional results can be actually achieved applying a scale system and an estimation of the appropriate scale factor”.
The practical application of this system has been employed for the manufacturing of the negative part, in the electroforming process, for the manufacturing of supported electrodes, in the electroforming process, by the Centre of Integrated Manufacturing in the University of Las Palmas de Gran Canaria.
This Project has been partially supported by the Science and Education Ministry into the Applied Research National Program (CIT-420000-
Photo:
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