Statistical evaluation of the strength of wear-resistant hard coatings

Strength of physically vapor deposited (PVD) titanium nitride (TiN) coating was characterized by bending test of free-standing film. By solving an inverse problem to optimize the distribution of equivalent cracks with respect to the failure probability of specimens, strength of unit surface areas was successfully evaluated. The average strength of interface side and growing side surface for the unit area of 1 μm2 were 3.87 GPa and 2.60 GPa, respectively, which were the data first reported.