Nanoindentation on soft film/hard substrate and hard film/soft substrate material systems with finite element analysis

Amorphous niobium oxide thin films

“…Saha et al [65] found that the "true" hardness of aluminum films on different hard substrates could be obtained for 0.05 b h/t b 0.2, where h is the penetration and t the film thickness. Similarly, Pelegri and Haung [66] by finite element analysis found a "true" hardness for h/t between 0.05 and 0.45, while Beegan et al [63] reported the influence of the substrate for all h/t values. Thus considering that it was not possible to measure indentations below h/t = 0.25, the reported hardness in this work might be somewhat overestimated.…”

Nanohardness and brittleness of irradiated spinel ceramics

“…less than half of the thickness of the modified layer. Accordingly to the analysis performed by Pelegri and Huang nanohardness measurements are not significantly affected by the unmodified bulk when the indentation depth is smaller than half of the thickness of the analyzed layer [5]. The load/unload curves recorded in nanohardness measurements were fitted using the Oliver-Pharr method [6].…”

Failure Behavior Characterization of Mo-Modified Ti Surface by Impact Test and Finite Element Analysis

“…The Hertzian shape of the distribution is retained during plastic deformation. Furthermore, compared to the monolayer hard film/soft substrate system, the stress decreases gradually along the thickness of the graded layer and changes slowly at the interface ( Ref 19,41). The graded layers, therefore, do not undergo adhesive failure, due to their ability to accommodate deformation.…”