The Brightlands Materials Center, a Netherlands-based research facility founded by TNO and the Province of Limburg, has developed 3D printed composite parts with self-sensing capabilities. The 3D printed composites, which were printed using Anisoprint’s composite AM platform, are programmed to sense their own condition, functioning as a real-time sensor. The innovative materials could be used in industries like aerospace, construction and healthcare, where they could monitor critical structures.
Leveraging its extensive materials knowledge, a team from the Brightlands Materials Center found a way to combine self-sensing properties in continuous fiber with additive manufacturing. Polymer-matrix composites with continuous carbon fiber can sense their condition thanks to the measurable changes in electrical resistance in the fibers. These materials are sometimes used in airplanes or critical structures like bridges, where structural integrity is paramount and needs to be monitored. Usually, however, self-sensing composites are manufactured using conventional processes which are complex and require specialized equipment.
In developing a way to 3D print self-sensing composite parts, the Brightlands team aims to make the technology more effective and accessible. One of the the advantages of additive manufacturing is that it enables the precise positioning and orientation of carbon fibers, which means that the fiber sensors can be placed exactly where they are needed, and multiple fibers can be positioned to create an array of sensors within the part.
The 3D printed composite method was demonstrated when the Brightlands team 3D printed two test parts, a miniature pedestrian bridge and a simple bending beam (above), using Anisoprint’s Composer A4 composite 3D printer. Both parts integrated specific fiber alignments, focusing on the integral locations in each geometry. Notably, the fibers were designed to “stick out” of the part, enabling electronic hardware to monitor the condition changes.
This approach of 3D printing self-sensing composites could make it easier to monitor conditions in critical structures, especially in the prototyping phase. The 3D printed composite prototypes could be valuable in self-sensing the real dynamics and forces that a product or structure needs to withstand, giving designers and engineers a better understanding of how the 3D printed parts will need to perform.
These advanced materials could be used in the aerospace industry in designing aircraft parts or in construction for critical structures like bridges. In the medical sphere, the 3D printed self-sensing composites could reportedly be used as a diagnosis tool, helping to provide information about stress distribution and movement patterns to doctors.