A medical implant device or component thereof comprising a metal substrate and a coating layer structure provided on the substrate. The coating layer structure comprises an outermost layer of a ceramic material. A bonding structure is deposited between the metal substrate and the coating layer structure. The bonding structure comprises a chromium rich layer, which is deposited onto the metal substrate surface and has a higher concentration of chromium than the metal substrate, as well as a gradient layer having a composition gradient from the chromium rich layer towards the surface of the device providing increasing proportions of a gradient material which has structural correspondence with the layer of the coating layer structure that is most adjacent to the bonding structure.