Titanium-nitride (TiN) ceramic coatings are widely utilized to extend the lifetime of mechanical parts under severely abrasive conditions and in lubrication environment. Since ceramic layers coated on machinery components inevitably experience the changes in their properties, it is necessary to evaluate the characteristics of ceramic coating layers nondestructively for the reliable use of coated components and the remaining life prediction. For this purpose, in the present study, the ultrasonic backward radiation technique is applied to evaluate very thin TiN ceramic layers coated on AISI 1045 steel and austenitic 304 steel substrates. In this study, very interesting behaviors are revealed from the interrogated TiN ceramic coated specimens. The sliding loading in the abrasive wear regime increases the peak amplitude of the profile. However, the sliding loading large enough to produce scuffing finally decreases the peak amplitude of the profile while the peak angle increases.