Property evaluation of vapor-deposited TiN film by the analysis of elastic waves: (2nd report, film strength estimated by AE source inversion during compressive loading)

Damage progression of vapor-deposited TiN films on SUS317J2 steel under compressive loading was estimated by continuous monitoring of acoustic emission (AE). AE source inversion revealed that the film fracture progresses as follows: (1) Mode-II delamination at the edge of the TiN film during elastic strain, (2) Mode-I delamination of TiN due to the emergence of a slip step in the plastic region, and (3) Mode-I film fracture which allows the penetration of corrodent. The threshold strain that causes film damage was correlated with the mismatch of the elastic modulus of the TiN film to that of the substrate metal.