TRIBOLOGICAL BEHAVIOUR OF PULSED ELECTRODEPOSITED Ni-W-SiC NANOCOMPOSITES

Electrodeposited Ni-W alloy composite coatings have the potential to be a promising alternative for hard chrome replacement due to it hardness, high temperture thermal stability and process economy.  The present study focuses on the deveopment of Ni-W-Sic alloy nano composite coating employig a novel pulsed electrodeposition techniques from citrate bath.  The influence of duty cycle and pulse frequency on the incorporation of SiC particles, mechanical properties of Ni-W alloy coatings has been studies in as deposited and heat treated conditions.  The coatings were characterized using XRD, SEM and TEM.  Finally, the tribological properties of Ni-W-SiC nano-composite on the sliding wear resistance as function of SiC content has been studied in comparision with hard chrome and comercial NIKASIL coatings.  The nanocomposite Ni-W-SiC nanocomposite coatings demonstrated improved wear resistance over hard chrome and NIKASIL coatings