The indentation modulus was higher than the tensile modulus by a factor of at least three.
Usually, the indentation modulus has the same value as Young's modulus.
Then, the Martens hardness (HM), the Vickers hardness (HVIT) based on indentation hardness (H IT), the indentation modulus (E IT), the ratio of elastic to total work (η IT), and the traditional Vickers hardness (HV1) were measured by IIT.
The steeper the unloading curve the higher the indentation modulus (E IT).
Force-indentation depth curves were recorded (Fig. 2), and the Martens hardness (HM), the indentation modulus (EIT), and the percentage of the elastic part of indentation work, known as elastic index (ηIT), were measured according to the ISO 14577-1 [14].
The elastic and plastic works were highlighted by different shadings of corresponding areas while tangent to unloading curve is used for the characterization of the indentation modulus (E IT).
Dependence of a the indentation modulus E ind on the bulk modulus B and of b the surface energy γ on the cohesive energy E coh.
Moreover, to measure the indentation modulus and hardness of copper more precisely, McElhaney et al. [11] proposed a novel method to measure the contact area by taking into account the influence of inherent pile-up and sink-in in the indentation experiment of polycrystalline copper.
Microhardness of the Futura coating was ca. 3000 HV while the indentation modulus was ca. 425 GPa.
The values of the indentation modulus and of the hardness in the newly formed bone of the β-APN treated tissues are decreased by 35% (p < 0.001) and 40% (p < 0.003), respectively, compared to control samples in areas with 19 wt.% calcium or less, which typically correspond to newly formed bone.
