4DPrintEN project enters its final stage

Main aim of 4DPrintEN project is the development of the manufacturing process through 3D printing of portable and intelligent devices with low consumption that are capable of generating different voltages in response to external stimulus, with the intention of capturing and collecting electrical energy in an efficient way.

The multidisciplinary consortium that works in achieving this objective comprises Spanish and Romanian companies and public institutions: Izertis, Bucharest National Institute of Physics of Materials (NIMP), All Green, Intelectro, the Technical University Gheorghe Asachi of Iasi and Idonial technological center.

During the first year of project execution, the development of the material was carried out, which had to comply with very specific electrical, mechanical and thermal properties. In particular, six experimental models of polymeric composite materials were obtained using a two-component matrix made up of PP (polypropylene) and TPU (thermoplastic polyurethane) and with BaTiO3 powder with a diameter of less than 2 µm as reinforcement in different proportions, on which different analysis were carried out in order to select the three models most appropriate for the project.

Afterwards, the material filamentation process was developed, for which two different techniques were used: injection and extrusion, with the aim of achieving 5 different types of filaments of a constant diameter that could be used to feed the 3D printer.

As it is a new material, a new 3D printing and characterization process also had to be developed. The first step was to check the printability of the filamented materials and to determine the optimum printing temperatures and speeds for all of them. Once the values with the best results were obtained, the rest of the relevant printing parameters were analyzed and established (layer height, fill percentage and angle, number of skirts...), adjusting them to ensure that the pieces to be manufactured had the best finish and as much functionality as possible.

To validate this process, two different types of parts were manufactured, a circuit and a mesh, using the 5 filaments developed, which also made it possible to determine which of these filaments were the most suitable for 3D printing, since not all of them behave the same or, therefore, allow to manufacture parts of the same quality.

During 2021, and until the end of the project in March, the activities carried out have comprised testing the 3D printed parts by conducting piezoelectric and preparing an exploitation plan of the project results based on the conclusions obtained and their possible application in marketable products.

Among targeted applications of the results of 4DPrintEN project is the development of medical devices that capture and subsequently convert biomechanical energy into electric energy, so no batteries will be needed. Instead, pacemakers would be charged by heartbeats, deep-brain implants by electric impulses, cochlear implants by inner ear vibrations, or bone implants could stimulate tissue repair.

Another possible application is the development of wearable active textiles for physiology-based thermal management.

4DPrintEN is a project framed within the MANUNET Transnational Call 2018 program, which is possible to carry out thanks to the funding obtained from UEFISCDI in Romania and IDEPA in Asturias.