“Additive manufacturing represents the new industrial revolution, an innovative process that is constantly growing ” Prof. Ferdinando Auricchio – Coordinator Of the University of Pavia Research Group
Among the most widely used 3D printing technologies in the industrial sector, molten deposition (FDM) modelling plays a very important role, not only for the production of representative 3D models, but mainly thanks to the development of new materials such as PEEK and ULTEM, fundamental to the needs of complex markets (such as automotive and aerospace)as well as for the ability to make structurally functional components.
The University of Pavia has been active since 2011 in the research process in additives and since 2017 the University is the founder of the project”Virtual Modeling and Additive Manufacturing (3D printing) for Advanced Materials”, carried out thanks to an internal 3D printing laboratory, to dedicate an interesting study to the characteristics of finished components.
For its great reliability, print quality, multi-extruder process management and wide range of available materials, the University of Pavia Research Team chose to use 3ntr 3D printers during the entire phase of the research project .
What is the project and what are the results? Interview with Professor Ferdinando Auricchio, Coordinator of the Research Group – University of Pavia.
3D printers used: 3ntr A4V2 and V3 3 extruders
Materials used: ABS, HIPS
What motivations prompted the team of researchers at the University of Pavia to start an additive research project?
F.A. – The main motivation is the growing industrial interest in additive manufacturing technologies. Every economic forecast is in fact agreed that additive manufacturing represents a real revolution in the industrial world. Moreover, as a relatively young technology is still a very young technology, there are still many aspects to be investigated and investigated, and research in this area is essential to be able to make new solutions available to companies in terms of technologies and materials.
What motivated you to choose FDM technology for research?
F.A. – FDM 3D printing technology is one of the most popular technologies, thanks in part to being more economically accessible than other technologies, while offering the greater flexibility in terms of usable polymers. Our research has focused on 3D FDM printing because, thanks to recent developments in new materials such as fibro-reinforced technopolymers, it can be used to produce structural components that in many cases have replaced other components typically produced in light metals, such as aluminium.
How did the University of Pavia get to know 3ntr 3D printing technology and how was it instrumental in the project?
F.A. – 3ntr technology has been fundamental in two respects: from a technical point of view the machines have a heated plate and room and the ability to mount three extruders. From a software perspective, it has advanced, easy and intuitive slicing software that makes it easy to manage print parameters and multi-extruder processes.
What was the concrete contribution of 3D 3ntr printers in the course of the project?
F.A. – The heated room and plate allowed the model of the bridge to be printed, avoiding distortions and detachments from the printing plate, while the presence of two extruders allowed the use of a different material for the support structures, allowing an easy detachment of the model at the end of printing.
How were 3D 3ntr printers integrated into the research project?
F.A. – 3ntr 3D printers(A4V3 ndr) were used for the production of the bridge model and the flat spring in ABS, which were the main subject of the research. In particular for the model of the bridge, the hot room was essential to avoid distortions and consequent detachments of the plate during printing, while the second extruder allowed to use a special polymer for the realization of the support structures, easily removable.
Let’s get to the heart of the project: what were the objectives and what results were achieved?
F.A. – The project lasted about 9 months. The main purpose was to develop an FEM simulation method based on sequential element activation, which could predict stress and distortion on 3D printed pieces with FDM technology. 3ntr 3D printers allowed us to produce the models in ABS and thanks to a reconstruction made with 3D laser scanners it was possible to compare the deformed models with those measured experimentally. This comparison allowed us to validate the numerical results and show that our simulation approach with 3ntr 3D printers is sustainable and brings results that deviate from reality no more than 10%.
Particularly interesting, for the development of the use of 3D printing in manufacturing, is the possibility of predicting residual distortions and/or stress accumulations and this can have great industrial relevance because it saves resources in terms of time and cost by ensuring the possibility of predicting imperfections and possible errors.
F.A. – We plan to enrich our simulation approach with the introduction of a cohesive model that allows us to predict any detachment of FDM components during the printing phase, thus avoiding the prior interruption.
We thank for the collaboration Professor Ferdinando Auricchio, Coordinator Research Group and expert in constitutive models of materials and numerical simulations through software to the finished elements, Dr. Alberto Cattenone, Dr. Gianluca Alaimo and the Dr. Simone Morganti.