Sintering and mechanical properties of mechanically milled Inconel 625 superalloy and its composite reinforced by carbon nanotube

Carbon nanotubes showing tensile strength up to 20 GPa and stiffness up to 1000 GPa, are the strongest fibers known to mankind, which has been proved to be an extraordinary filler for light metals such as aluminium and titanium metals and alloys. However, the efficiency of its reinforcement to hard metallic materials such as Nickel-based superalloys are still unknown and under developed in the current powder metallurgy research. This study focuses on the sintering and mechanical properties of carbon nanotube reinforced Inconel 625 superalloy. The carbon nanotube modified Inconel 625 powder was pressed with a polymer binder and sintered to achieve high density. The mechanical properties are measured and compared with non-reinforced counterparts to verify the efficiency of carbon nanotube reinforcement. The mechanism of such reinforcement will be discussed based on the optical image and nano-indentation analysis.