Correlation between nanoindentation and nanoscratch properties of carbon nanotube reinforced aluminum composite coatings

Nanoindentation and nanoscratch experiments are conducted on cold-sprayed aluminum composite coatings reinforced with and without carbon nanotubes (CNTs). Analytical model is developed to correlate nanoscale mechanical and tribological properties of the solid material. The geometry factor of Berkovich tip and its orientation during nanoscratch is taken into account to describe the deformation behavior of the solid material underneath indenter. Nanoindentation and nanoscratch experiments in conjunction with the computed results illustrate that the addition of carbon nanotubes into aluminum matrix contributes to increase in elastic modulus, hardness, yield strength, shear strength and nanoscale wear resistance. The coefficient of friction is unaffected by the addition of CNTs up to 1 wt.%.