Films of Ti, TiN and Ti/TiN were deposited on pure iron substrates by ion plating. Interface analyses were carried out by means of depth-selective conversion electron Mössbauer spectroscopy. The mechanical behaviour of TiN films was investigated by scratch and U-bend tests. Ti interacts with the iron substrate, giving rise to α-Fe(Ti) and α-Ti(Fe) solid solutions, as well as to TiFe 2 and TiFe intermetallic compounds. The solid solutions account for the increased TiN-Fe bonding and the improved mechanical behaviour of TiN.