Thermal manipulation of carbon nanotube fiber by mechanical stretching

Thermal manipulation of materials is of great interest due to various requirements for heat dissipation. We report an experimental study of thermal manipulation of a highly oriented carbon nanotube (CNT) fiber by mechanical stretching based on the transient electro-thermal (TET) method. The thermal property of CNT fibers is measured under different elongation ratios and temperatures. Thermal conductivity enhancement as high as 28% is observed at all temperatures with applied mechanical stretching less than 5% in the axial direction. This enhancement in thermal conductivity is attributed to the better CNT alignment and the reduction in thermal resistance at CNT contacts, which is validated by the density/structural analysis.