Adhesion of electrodeposited nanocrystalline Ni–W coatings on Cu

A study was performed on the adhesion of nanocrystalline Ni–W alloy coatings, on copper, with the help of a scratch testing apparatus. The nanocrystalline Ni–W coatings were electrodeposited on copper substrates. The tungsten content in the Ni–W alloy coating was found to be 42 wt-% (19 at.-%). The results obtained from the scratch experiments showed that the nanocrystalline Ni–W coatings on copper suffer tensile failure and minor delamination. The mean cohesive and adhesive critical loads were found to be in the range of 19–85 N and 34–102 N, respectively and to increase with increasing thickness of the coatings.