Electrodeposited CoW alloy and CoW–WC nanocomposite coatings were produced and investigated under dry and wet sliding conditions. Incorporation of WC nanoparticles (average size 500 nm) into CoW matrix improves the hardness and coefficient of friction. The measured wear volume of CoW–WC
nanocomposites under dry sliding was almost half of the one on CoW coatings. Under wet sliding in a 0.5 M NaCl solution at room temperature, the open circuit potential recorded on both CoW–WC nanocomposites and CoW alloys during sliding became nobler compared to starting point but it dropped suddenly down to active potential region after counter body retrieval.