AM@UU Seminar - 4D Printed Nitinol Smart Braided Medical Devices

Please register no later than the 3rd of March here

Date/Time: 5th of March @ 15:15 (CET)

Place: 2004, Ångström / Broadcasting on Zoom

Invited Speaker: Jon Molina-Aldareguia, Director, IMDEA Materials Institute, Professor Additive Manufacturing, Universidad Politécnica de Madrid, Spain

Additive manufacturing (AM) technologies have reinvented many areas of product development. In the medical field, the ability to promote patient personalization has become a key factor. AM technologies allow the manufacturing, based on medical images, of models for surgical planning, surgical guides and even, implants and porous scaffolds for tissue regeneration.

However, many of these applications are static and do not allow a dynamic interaction, which would enable minimally invasive surgeries. or allow shape changes according to the healing process of the tissue. The use of "smart" medical devices, obtained through the emerging concept of "4D printing", capable of undergoing progressive metamorphosis according to surgical procedures, biological integration and/or healing processes, is still a dream, especially in metallic materials that offer substantial load bearing capabilities. The AM of smart metallic alloys, like nitinol, might offer solutions in this area.

Full control solid freeform fabrication of superelastic nitinol is demonstrated in this study, enabling the creation of a new generation of personalized medical devices. The engineering strategy stands out for a pioneering algorithmic design of lattices and wovens, which can be adjusted to anatomical surfaces and whose mechanical properties can be controlled at will, enabling functional gradients of stiffness and transitions between lattices and wovens. Implementation of the engineering solution was possible by the optimization of laser powder bed fusion (LPBF) of NiTi powders, combined with a set of post-processing techniques, including chemical etching and electropolishing, that enable the manufacture of algorithmic designs and further contribute to achieving the superelasticity required for the crimpability of minimally invasive transcatheter devices (MITDs).

Following the proposed approach, minimally invasive surgeries may be fostered for several types of MITDs, including stents, transcatheter aortic valve replacements, customized shape clot retrievers for thrombectomy, tapered flow diverters, braided bifurcations, and fenestrated stents, among other possibilities. These advances and designs are expected to open new horizons in personalized approaches for cardiovascular and neurological surgery.

Prof. Molina will also act as opponent on 6th March at 9.15 in 10132, Ångström, Häggsalen for the defence of Lisa Larsson on "Additive Manufacturing of Biodegradable Magnesium Alloy WE43: Linking Process Parameters to Microstructure and Mechanical Performance."