Resistance Temperature Detectors Fabricated via Dual Fused Deposition Modeling of Polylactic Acid and Polylactic Acid/Carbon Black Composites

• Published in: Sensors (Basel, Switzerland) Vol. 21; no. 5; p. 1560
• Main Authors: Jeon, Jei Gyeong, Hong, Gwang-Wook, Park, Hong-Geun, Lee, Sun Kon, Kim, Joo-Hyung, Kang, Tae June
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 24-02-2021; MDPI AG
• Subjects: 3D printing; Communication; polylactic acid; polylactic acid/carbon black composites; polymer-matrix composites; temperature detection; temperature detection; polymer-matrix composites; polylactic acid; 3D printing; polylactic acid/carbon black composites
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s21051560

Planar-type resistance temperature detectors (P-RTDs) were fabricated via fused deposition modeling by dual nozzle extrusion. The temperature-sensing element of the fabricated sensor was printed with electrically conductive polylactic acid/carbon black (PLA/CB) composite, while the structural support was printed with a PLA insulator. The temperature-dependent resistivity change of PLA/CB was evaluated for different stacking sequences of PLA/CB layers printed with [0°/0°], [-45°/45°], and [0°/90°] plies. Compared to a PLA/CB filament used as 3D printing source material, the laminated structures exhibited a response over 3 times higher, showing a resistivity change from -10 to 40 Ω∙cm between -15 and 50 °C. Then, using the [0°/90°] plies stacking sequence, a P-RTD thermometer was fabricated in conjunction with a Wheatstone bridge circuit for temperature readouts. The P-RTD yielded a temperature coefficient of resistance of 6.62 %/°C with high stability over repeated cycles. Fabrication scalability was demonstrated by realizing a 3 × 3 array of P-RTDs, allowing the temperature profile detection of the surface in contact with heat sources.