Favorable surface adhesion response of electrocrystallized nanohydroxyapatite on ultrafine-grained/nanograined austenitic stainless steel

We describe here the superior surface adhesion response of electrodeposited nanohydroxyapatite (nHA) on ultrafine-grained/nanograined austenitic stainless steel in relation to conventional coarse-grained structure, based on nanoscratching experiments using a nanoindenter. The superior surface adhesion response was consistent with the two primary factors, i.e. contact angle and surface roughness, that influence wettability. An accompanying aspect that emerged from the study is that the amorphous calcium phosphate nanoparticles with lower activation energy barrier are precursors to the nucleation of vein-type interconnected nHA.