The local mechanical properties of cells are frequently probed by force indentation experiments carried out with an atomic force microscope. Application of common contact models provides a single parameter, the Young's modulus, to describe the elastic properties of cells. The viscoelastic response of cells, however, is generally measured in separate microrheological experiments that provide com...

The lack of practicable nonlinear elastic contact models frequently compels the inappropriate use of Hertzian models in analyzing indentation data and likely contributes to inconsistencies associated with the results of biological atomic force microscopy measurements. We derived and validated with the aid of the finite element method force-indentation relations based on a number of hyperelastic...

Simple relations for the onset of competing brittle and quasiplastic damage modes in Hertzian contact are presented. The formulations are expressed in terms of well-documented material parameters, elastic modulus, toughness, and hardness, enabling a priori predictions for given ceramics and indenter radii. Data from a range of selected ceramic (and other) materials are used to demonstrate the a...

The objective of this study is to explore and compare the mechanical response AlCrSiN coatings deposited on two different substrates, namely, WC-Co cBN. Nano-indentation was used measure hardness elastic modulus coatings, micro-indentation for observing contact damage under Hertzian with monotonic cyclic (fatigue) loads. Microscratch tests were also evaluate strength adhesion between substrates...

This study aimed to quantify the biomechanical properties of murine meniscus surface. Atomic force microscopy (AFM)-based nanoindentation was performed on the central region, proximal side of menisci from 6- to 24-week old male C57BL/6 mice using microspherical tips (Rtip≈5µm) in PBS. A unique, linear correlation between indentation depth, D, and response force, F, was found on menisci from all...

OBJECTIVES/METHODS From a materials scientist's perspective, dental materials used for tooth repair should exhibit compatible mechanical properties. Fulfillment of this criterion is complicated by the fact that teeth have a hierarchical structure with changing mechanical behavior at different length scales. In this study, nanoindentation with an 8 microm spherical indenter was used to determine...

In this article, we present a quantitative stiffness imaging technique and demonstrate its use to directly map the dynamic mechanical properties of materials with nanometer-scale lateral resolution. For the experiments, we use a ‘‘hybrid’’ nanoindenter, coupling depth-sensing nanoindentation with scanning probe imaging capabilities. Force modulation electronics have been added, enhancing instru...

AFM microor nanoindentation is a powerful technique for mapping the elasticity of materials at high resolution. When applied to soft matter, however, its accuracy is equivocal. The sources of the uncertainty can be methodological or analytical in nature. In this paper, we address the lack of practicable nonlinear elastic contact models, which frequently compels the use of Hertzian models in ana...

This study aimed to quantify the biomechanical properties of murine meniscus surface. Atomic forcemicroscopy (AFM)-based nanoindentation was performed on the central region, proximal side of meniscifrom 6to 24-week old male C57BL/6 mice using microspherical tips(RtipE5 mm) in PBS. A unique,linear correlation between indentation depth, D, and response force, F, was found on menis...

We deal with rolling contact between quasi-identical bodies. As normal and tangential problems are uncoupled in that case, the simplified approach to determine contact area and normal loading distribution for rolling contact problems is presented in a first part. In the second part, the solution of the tangential problem is used to reactualised the rolling profiles and enables to follow the wea...