Publications associées à Nanoindentation

Nanoindentation of embedded particles

Andreas Mortensen, Alejandra Inés Slagter, Joris Pierre Everaerts

We address the effect of elastic inhomogeneity on elastic modulus and hardness determinations made by depth-sensing indentations performed on individual particles embedded within a matrix of different elastic modulus. Finite element simulations and nanoind ...

SPRINGER HEIDELBERG2023

Dynamic study of contact damping in martensitic stainless steels using nano-indentation

Philippe Spätig, Hans-Peter Seifert

The study was undertaken to gain insight into the micro-mechanisms controlling plasticity at the micrometer scale of elastic-plastic metallic alloys. Dynamic nano-indentation tests, where a small harmonic force amplitude is superimposed during loading, ref ...

ELSEVIER2020

Depth-dependent mechanical properties of human articular cartilage obtained by indentation measurements

Pierre-Etienne Bourban, Lee Ann Laurent-Applegate, Matteo Gregorio Modesto Marascio, Robin Martin, Jens Antons

Emerging 3D printing technology permits innovative approaches to manufacture cartilage scaffolds associated with layer-by-layer mechanical property adaptation. However, information about gradients of mechanical properties in human articular cartilage is li ...

2018

Mechanical properties of MC multimetallic carbides in steel

Lionel Michelet

Carbides constitute a class of materials used for many applications, where excellent mechanical properties, such as stiffness, hardness and fracture toughness, are required. The machining industry is a typical example where carbide are crucial materials. W ...

EPFL2018

Helium effects on irradiation assisted stress corrosion cracking susceptibility of 316L austenitic stainless steel

Ignasi Villacampa Roses

The formation and growth of cracks by irradiation assisted stress corrosion cracking (IASCC) in light water reactor internals is a critical issue for a safe long-term operation of nuclear power plants. The IASCC susceptibility at relatively low dose is dom ...

EPFL2018

On the mechanical characteristics of a self-setting calcium phosphate cement

John Botsis, Luis Pablo Canal Casado, Dimitrios Karalekas, Alexios Bimis

Objective: To perform a mechanical characterization of a self-setting calcium phosphate cement in function of the immersion time in Ringer solution. Materials and methods: Specimens of self-setting calcium phosphate cement were prepared from pure alpha-TCP ...

Elsevier2017

Mechanical properties of tailored nanostructured alloys produced by electrodeposition

Juri Aljoscha Wehrs

The studies presented in this thesis aim to extend the current knowledge and understanding of the mechanical behavior of nanocrystalline materials with respect to temperature- and time dependence. Free standing electrodeposited nanocrystalline nickel speci ...

EPFL2017

A Compressible Scaffold for Minimally Invasive Delivery of Large Intact Neuronal Networks

Philippe Renaud, Georg Fantner, Thomas Michael Braschler, Patrick Fraering, Oliver Peric, Sébastien Mosser, Amélie Barbara Hildegarde Béduer, Sidi Ahmed Bencherif

Millimeter to centimeter-sized injectable neural scaffolds based on macroporous cryogels are presented. The polymer-scaffolds are made from alginate and carboxymethyl-cellulose by a novel simple one-pot cryosynthesis. They allow surgical sterility by means ...

Wiley-VCH Verlag2015

Twist and Stretch of Helices Explained via the Kirchhoff-Love Rod Model of Elastic Filaments

John Maddocks

In various single-molecule experiments, a chiral polymer, such as DNA, is simultaneously pulled and twisted. We address an elementary but fundamental question raised by various authors: does the molecule overwind or unwind under tension? We show that withi ...

Amer Physical Soc2013

Microstructure and mechanical properties of a W-2wt.%Y2O3 composite produced by sintering and hot forging

Nadine Baluc, Philippe Spätig, Robin Schäublin

A W-2Y(2)O(3) composite has been developed by powder metallurgy methods in collaboration with the Plansee Company (Austria). The microstructure of the composite was analyzed using transmission electron microscopy and electron backscatter diffraction in sca ...

2013

Influence of the meso-structure in dynamic fracture simulation of concrete under tensile loading

Jean-François Molinari, Leonardo Snozzi

We investigate the dynamic behavior of concrete in relation to its composition within a computational framework (FEM). Concrete is modeled using a meso-mechanical approach in which aggregates and mortar are represented explicitly. Both continuum phases are ...

Pergamon-Elsevier Science Ltd2011

Numerical study of the effect of confining stress on rock fragmentation by TBM cutters

Lijun Yin, Hongsu Ma

This paper investigates the effect of confining stress on rock fragmentation under TBM cutters by numerical simulation. Firstly, based on the characteristics of the force-penetration curve, the confining stress conditions for TBM tunneling are divided into ...

2011

Analyse non-linéaire des coques géodésiques multicouches à joints semi-rigides

Julius Natterer

In the 90ies the IBOIS-EPFL developed a new kind of shell structure. The ribs were made with simple boards waved together to form a spatial rib shell. However, the engineer currently does not have any effective method to calculate these kinds of spatial st ...

EPFL2010

Stiffness Tomography by Atomic Force Microscopy

Giovanni Dietler, Sandor Kasas, Serguei Sekatski, Charles Roduit

The atomic force microscope is a convenient tool to probe living samples at the nanometric scale. Among its numerous capabilities, the instrument can be operated as a namo-indenter to gather information about the mechanical properties of the sample. In thi ...

2009

A displacement sensing nanoindentation study of tribo-mechanical properties of the Ni-Co system

Andrzej Kulik

An analysis of the tribo-mechanical properties of the Ni-Co system, at the submicrometric contact scale, is conducted using displacement sensing nanoindentation. In particular, the influence of contact depth and surface finishing methods on the hardness, H ...

2008

Stiffness tomography by atomic force microscopy

Sandor Kasas, Charles Roduit

A method of analyzing a sample with a probe based measurement instrument using stiffness tomography. Stiffness or elastic modulus data obtained through contact measurement with the sample as a function of depth is used in the detection of features, particu ...

2007

Atomic force microscopy studies of nanotribology and nanomechanics

Ismaël Palaci

This thesis comes within the scope of tribology studies at the nanometer scale. The experimental techniques used in this work are essentially related to atomic force microscopy, which gives a direct access to the topography and forces of the studied system ...

EPFL2007

Footprints of deformation mechanisms during in-situ x-ray diffraction : nanocrystalline and ultrafine grainded materials

Nanocrystalline metals have been an area of great interest in recent years due to their enhanced characteristics. One of the most striking is implied by the Hall-Petch relation: with decreasing grain size the material becomes stronger. This promise is fulf ...

EPFL2006

Observation of fracture and plastic deformation during indentation and scratching inside the scanning electron microscope

Jean-Marc Breguet, Franz-Josef Haug, Sven Nico Stauss, Johann Michler

During nanoindentation measurements of thin films the formation of cracks within the film as well as of pile-up or sink-in around the indent are known to affect significantly the precision of hardness and Young's modulus values. The crack pattern in brittl ...

2004

Polyelectrolyte-based immunprotection systems : polymer purification and surface analysis

Dianelys Sainz Vidal

The research of this doctoral thesis was dedicated to polyelectrolytes, specifically to hydrogel materials, which result from coacervation and polyelectrolyte complex formation and have a potential as immunoprotection systems. In particular, microspheres o ...

EPFL2004