Thermomechanical behavior of carbon nanofibers for space applications
(NASA EPSCoR award)

Deformation and fracture of cone-stacked carbon nanofibers at elevated temperature. We focus on building an atomistic model of carbon nanofiber (CNF) with cone-stacked structure. CNFs have drawn increasing scientific and technological interest due to their unique, superior electronic and mechanical properties in comparison to microscale fibers. We have developed a method to create the structure of carbon nanocones (CNCs), the repeat unit structure in CNFs. A conical structure can be geometrically constructed by a “cut and glue” process, known as Volterra process. Usually CNCs are characterized by their cone angle. Only five types CNCs with cone angles of 19°, 39°, 60°, 85°, and 113° can be created from the corresponding continuous cone sheets with disclination angles of 60°, 120°, 180°, 240°, and 300°, respectively. Here, a typical nanocone sheet with a 60° disclination angle and the corresponding CNC with the cone angle of 113°, which is the largest angle observed experimentally and theoretically, are shown in the Figure below.

 

 
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