Session: 04-23-01: Process Development, Characterization, and Optimization for Additive, Subtractive, and Hybrid Manufacturing

Paper Number: 173920

Effect of Printing Parameters on Piezometric Properties in Additively Manufactured Nylon12 Carbon Fiber Composites for Cryogenic Environments 

Reliable sensing and structural health monitoring in cryogenic environments, such as those found in aerospace fuel tanks, space vehicles, and cryogenic propulsion systems, requires materials that are not only mechanically robust but also capable of detecting strain or damage in real time. Additively manufactured short carbon fiber (SCF)-reinforced polymer composites offer an attractive solution due to their lightweight nature and piezometric (strain-responsive electrical) behavior. These materials combine the advantages of polymer matrix flexibility with the conductivity and stiffness imparted by carbon fibers, enabling potential dual functionality as both structural and sensing components. However, the piezometric response of these materials under cryogenic conditions remains poorly understood, particularly with respect to how manufacturing parameters affect their multifunctional performance. 

This study investigates the influence of key fused filament fabrication (FFF) parameters, including print orientation, print speed, layer height, and bed temperature, on the mechanical and piezometric properties of nylon 12 SCF composites at 77 K, achieved through immersion in liquid nitrogen. A combination of tensile testing and in-situ piezoresistance measurements was used to evaluate performance under cryogenic conditions. These methods allow for simultaneous assessment of mechanical integrity and piezo response during deformation. Microstructural analysis further highlights how changes in fiber alignment, interlayer adhesion, and interfacial bonding influence both mechanical behavior and piezo responsiveness at low temperatures. Notably, variations in print orientation and layer height were found to significantly affect fiber distribution and conductive pathways, which in turn impact the gauge factor and mechanical strength of the printed specimens. 

These findings provide critical insight into tailoring print parameters during additive manufacturing to optimize multifunctional performance. The ability to fine-tune mechanical strength and piezo properties through processing conditions opens new pathways for designing materials that are both structurally sound and capable of real-time diagnostics in harsh environments. Potential applications for such cryogenically robust piezometric composites include real-time structural health monitoring of cryogenic tanks, pipelines, and propulsion systems; embedded sensing in thermal protection systems for space vehicles; and adaptive components capable of detecting and responding to strain or damage under extreme thermal and mechanical loads. 

This work provides one of the first comprehensive analyses of cryogenic piezometric behavior in additively manufactured nylon 12 with SCF composites. By linking print parameters to microstructural evolution and multifunctional performance at low temperatures, the study identifies key factors that influence sensing capability and mechanical reliability. These findings advance the development of smart composite materials for embedded sensing and adaptive performance in extreme thermal environments. 

 

Presenting Author: Tiana Tonge Washington State University

Presenting Author Biography: Tiana Tonge is a Ph.D. Candidate in the school of Mechanical and Materials Engineering at Washington State University. Her research primarily focuses on characterizing cryogenic materials to advance the performance and reliability of structures used in extremely low-temperature environments. Specifically, she investigates how materials produced through additive manufacturing behave under cryogenic conditions, with applications spanning pipelines, fuel tanks, aerospace systems, and other critical infrastructure. Her work integrates experimental testing, characterization techniques, and computational modeling to develop a deeper understanding of material behavior and inform the design of safer, more efficient cryogenic components. She earned her Bachelor of Science in 2021 in Mechanical and Manufacturing Engineering from Oregon State University. Following her bachelor's studies, she gained experience in semiconductor manufacturing and management, contributing to production line workflow. Her collaborative research has resulted in a conference publication.

Authors:

Tiana Tonge Washington State University
Satyajit Mojumder Washington State University