Nanoindentation is usually applied on thin films at ambient temperatures for hardness determination. Recently, instruments for conducting nanoindentation at elevated temperatures have been developed facilitating measurements up to 700 oC. Both indenter and specimen, if necessary, are heated in an inert atmosphere to avoid film oxidations. In the described investigations, nanoindentations were conducted on cemented carbides and high speed steel specimens, coated with various films, up to 400 oC. The obtained results were subjected to statistical analysis to estimate their reliability. Moreover, the results were evaluated by appropriate FEM (Finite Element Method) algorithms for determining the coatings’ elasticity modulus, yield and rupture stress as well as hardness at various temperatures. The results reveal a non-linear temperature dependence of the coating properties
