Fabrication of a Low Density Carbon Fiber Foam and Its Characterization as a Strain Gauge

Materials

Claudia C. Luhrs¹  Chris D. Daskam¹  Edwin Gonzalez² 

[1] Mechanical and Aerospace Engineering Department, Naval Postgraduate School, 700 Dyer Rd., Monterey 93943, CA, USA; E-Mail:;Hartnell College, Salinas, CA—Naval Postgraduate School, Monterey 93943, CA, USA; E-Mail:

关键词: carbon nanofiber;    viscoelastic;    strain gauge;    low weight;    porous;    electrically conductive;    hydrophobic;   

DOI  :  10.3390/ma7053699

来源: mdpi

【 摘 要 】

Samples of carbon nano-fiber foam (CFF), essentially a 3D solid mat of intertwined nanofibers of pure carbon, were grown using the Constrained Formation of Fibrous Nanostructures (CoFFiN) process in a steel mold at 550 °C from a palladium particle catalysts exposed to fuel rich mixtures of ethylene and oxygen. The resulting material was studied using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Surface area analysis (BET), and Thermogravimetric Analysis (TGA). Transient and dynamic mechanical tests clearly demonstrated that the material is viscoelastic. Concomitant mechanical and electrical testing of samples revealed the material to have electrical properties appropriate for application as the sensing element of a strain gauge. The sample resistance versus strain values stabilize after a few compression cycles to show a perfectly linear relationship. Study of microstructure, mechanical and electrical properties of the low density samples confirm the uniqueness of the material: It is formed entirely of independent fibers of diverse diameters that interlock forming a tridimensional body that can be grown into different shapes and sizes at moderate temperatures. It regains its shape after loads are removed, is light weight, presents viscoelastic behavior, thermal stability up to 550 °C, hydrophobicity, and is electrically conductive.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland