Effect of sintering on mechanical and electrical properties of carbon nanotube based silver nanocomposites

Abstract

Nanocrystalline (single and multiwall) carbon nanotube reinforced silver nanocomposites are successfully synthesized by a modified molecular level mixing method. These materials are subsequently sintered up to 800 °C in inert atmosphere for 12 h. To elucidate the effect of sintering, micro-structural, mechanical and electrical properties of fabricated nanocomposites are evaluated before and after sintering. Scanning and transmission electron microscopic characterization have revealed that the carbon nanotubes are embedded, anchored and homogenously dispersed in silver matrix. Measured hardness and Young’s modulus of fabricated nanocomposites are increased by 20–30 % after sintering. The carbon nanotube reinforcement has also improved electrical conductivity of low conducting nano-silver matrix before sintering. However, negative reinforcement effect is observed in high conducting bulk silver matrix after sintering. Comparatively improved mechanical and electrical properties of single wall carbon nanotube reinforced nanocomposites than multiwall nanotube reinforced nanocomposite are observed, which are correlated with high aspect ratio and larger effective contact surface area of single wall carbon nanotubes.