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Search for "hardness" in Full Text gives 92 result(s) in Beilstein Journal of Nanotechnology.

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

  • Pia Sundberg and
  • Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

Graphical Abstract
  • , with a toughness of about 0.17 MPa·m0.5 [81]. The brittleness was also observed with nanointendation measurements, giving an elastic modulus of about 37 GPa and a Berkovich hardness of about 0.47 GPa [84]. However, when the TMA+EG hybrid with an additional H2O pulse was employed as an interlayer
  • , after which there was a larger drop to 1.5 Å per cycle at 135 °C. The TiCl4+EG hybrid thin films were unstable: The thickness diminished by 15% over five days and after 25 days the total reduction was 20%. The elastic modulus and hardness values measured by using nanointendation were extremely low, i.e
  • these films was between 130 and 210 °C. The GPC value at 130 °C was 2.8 Å per cycle and dropped with increasing temperature gradually to 2.1 Å per cycle at 210 °C. A small increase of film thickness was observed when thin films were exposed to air. The elastic modulus and hardness were both higher for
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Published 22 Jul 2014

A nanometric cushion for enhancing scratch and wear resistance of hard films

  • Katya Gotlib-Vainshtein,
  • Olga Girshevitz,
  • Chaim N. Sukenik,
  • David Barlam and
  • Sidney R. Cohen

Beilstein J. Nanotechnol. 2014, 5, 1005–1015, doi:10.3762/bjnano.5.114

Graphical Abstract
  • relatively low hardness values results in susceptibility to surface damage. Transparent polymers, for example, are widely used in ophthalmology and the automobile industry, but scratches degrade their optical and mechanical properties [4][5]. There are several ways to improve the scratch resistance of
  • scratch protection due to their hardness [6]. There are literature reports of the effect of hard-on-soft coatings wherein the soft component is only marginally softer and more compliant than the stiffer and harder film [12]. The softer underlying substrate is proposed to promote sliding and energy
  • . According to the ASTM standard G171 (03) – standard test method for scratch hardness of materials using a diamond stylus [33], scratch hardness changes inversely with the scratch width at a given load. In the work reported herein, a two-layer coating is used to alter the hardness and friction of a titania
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Published 10 Jul 2014

Molecular biology approaches in bioadhesion research

  • Marcelo Rodrigues,
  • Birgit Lengerer,
  • Thomas Ostermann and
  • Peter Ladurner

Beilstein J. Nanotechnol. 2014, 5, 983–993, doi:10.3762/bjnano.5.112

Graphical Abstract
  • vary depending on tissue hardness and size and must be empirically tested for every tissue. If permeability and transparency cannot be achieved in a whole mount specimen, it may be necessary to perform the ISH on tissue sections [48]. After pre-treatments of the tissue, the DIG-labelled RNA probe is
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Published 08 Jul 2014

Scale effects of nanomechanical properties and deformation behavior of Au nanoparticle and thin film using depth sensing nanoindentation

  • Dave Maharaj and
  • Bharat Bhushan

Beilstein J. Nanotechnol. 2014, 5, 822–836, doi:10.3762/bjnano.5.94

Graphical Abstract
  • tests (global deformation) were performed with a nanoindenter using a sharp Berkovich tip and a flat punch, respectively. Data from nanoindentation studies were compared with bulk to study scale effects. Nanoscale hardness of the film was found to be higher than the nanoparticles with both being higher
  • than bulk. Both nanoparticles and film showed increasing hardness for decreasing penetration depth. For the film, creep and strain rate effects were observed. In comparison of nanoindentation and compression tests, more pop-ins during loading were observed during the nanoindentation of nanoparticles
  • . Repeated compression tests of nanoparticles were performed that showed a strain hardening effect and increased pop-ins during subsequent loads. Keywords: gold (Au); Hall–Petch; hardness; nanoindentation; nano-objects; Introduction The characterization of mechanical properties is crucial for a fundamental
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Published 11 Jun 2014

Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone

  • Xiaohong Wang,
  • Heinz C. Schröder and
  • Werner E. G. Müller

Beilstein J. Nanotechnol. 2014, 5, 610–621, doi:10.3762/bjnano.5.72

Graphical Abstract
  • acid (Asp, D) and glutamic acid (Glu, E) [50]. The hardness, elastic modulus and creep of the two forms of the calcium carbonate deposits, the calcitic prisms and the round-shaped vaterite deposits were determined by nanoindentation. The load–displacement curves obtained for the two calcium carbonate
  • cells retain their capacity to synthesize HA crystallites. Furthermore, the mechanical properties, including surface roughness and hardness, of the hydrogel were determined. If silica is included in the hydrogel matrix, the encapsulated SaOS-2 cells were found to increasingly express the gene encoding
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Published 12 May 2014

Challenges in realizing ultraflat materials surfaces

  • Takashi Yatsui,
  • Wataru Nomura,
  • Fabrice Stehlin,
  • Olivier Soppera,
  • Makoto Naruse and
  • Motoichi Ohtsu

Beilstein J. Nanotechnol. 2013, 4, 875–885, doi:10.3762/bjnano.4.99

Graphical Abstract
  • substrate can be a serious problem, because substrates with large Ra values induce defects or dislocations in the deposited active layer [4]. Diamond is a promising material for future power devices because of its many excellent characteristics including high values for hardness and thermal conductivity
  • , and excellent semiconductor properties such as a high dielectric breakdown field and a high carrier mobility [5]. However, at the same time, the hardness of diamond makes it difficult to realize a flattened surface, and therefore the performance of diamond devices has not been as good as expected
  • . Furthermore, diamond is also a promising material for future quantum computing, because diamond with nitrogen vacancies can be a stable single-photon emitter at room temperature [6]. However, the high surface roughness of the diamond due to its hardness limits its performance. Conventionally, mechanical
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Published 11 Dec 2013

Dynamic nanoindentation by instrumented nanoindentation and force microscopy: a comparative review

  • Sidney R. Cohen and
  • Estelle Kalfon-Cohen

Beilstein J. Nanotechnol. 2013, 4, 815–833, doi:10.3762/bjnano.4.93

Graphical Abstract
  • curve by Oliver and Pharr (O&P) [23]. The latter developed a nanoindentation model and measurement protocol to quantitatively deduce the elastic modulus and the hardness of materials by loading an axisymmetric indenter into a sample while recording the applied force and displacement. The indenter “area
  • function” is determined by performing this experiment on a well-known material, typically fused quartz. The principle quantities derived from a nanoindentation experiment are elastic modulus and hardness. The former is a fundamental property of the material, which, in principle, can be calculated from bond
  • sample. Er is the reduced modulus which accounts for both sample and indenter Poisson ratio and modulus – υs, Es and υi, Ei respectively: Several depth sensing indentation methods were developed to evaluate A [23][24][25], which allow for evaluation of hardness and modulus without imaging the indentation
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Published 29 Nov 2013

AFM as an analysis tool for high-capacity sulfur cathodes for Li–S batteries

  • Renate Hiesgen,
  • Seniz Sörgel,
  • Rémi Costa,
  • Linus Carlé,
  • Ines Galm,
  • Natalia Cañas,
  • Brigitta Pascucci and
  • K. Andreas Friedrich

Beilstein J. Nanotechnol. 2013, 4, 611–624, doi:10.3762/bjnano.4.68

Graphical Abstract
  • sample that was coated by the doctor blade technique are displayed. Before cycling, the height differences are larger than in the SC-PVDF sample. However, the highest current of 1.7 nA is much smaller than the 30 nA measured at the SC-PVDF sample. Most of the surface has similar hardness and low energy
  • approximately 2–3 μm are visible, which possess a high hardness, no conductivity, and show low deformation and energy dissipation. The region in between these crystallites exhibits a finite but very small conductivity, one order of magnitude smaller than before cycling. Here, several small conductive soft
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Published 04 Oct 2013

Grating-assisted coupling to nanophotonic circuits in microcrystalline diamond thin films

  • Patrik Rath,
  • Svetlana Khasminskaya,
  • Christoph Nebel,
  • Christoph Wild and
  • Wolfram H.P. Pernice

Beilstein J. Nanotechnol. 2013, 4, 300–305, doi:10.3762/bjnano.4.33

Graphical Abstract
  • diamond has found a wealth of applications for the fabrication of windows that permit transmission in the long-IR or microwave regions [14]. In addition, diamond provides attractive material properties, such as biocompatibility, chemical inertness, high thermal conductivity, and mechanical hardness [15
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Published 07 May 2013

Size variation of infrared vibrational spectra from molecules to hydrogenated diamond nanocrystals: a density functional theory study

  • Mudar A. Abdulsattar

Beilstein J. Nanotechnol. 2013, 4, 262–268, doi:10.3762/bjnano.4.28

Graphical Abstract
  • extraordinary properties of bulk diamond that include high hardness, inertness and high thermal conductivity. The additional properties added by reduction to the nanoscale make diamonds and related carbon materials a focus for recent investigations [1][2][3][4][5][6][7][8][9]. One of the first steps of
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Published 15 Apr 2013

Effect of normal load and roughness on the nanoscale friction coefficient in the elastic and plastic contact regime

  • Aditya Kumar,
  • Thorsten Staedler and
  • Xin Jiang

Beilstein J. Nanotechnol. 2013, 4, 66–71, doi:10.3762/bjnano.4.7

Graphical Abstract
  • tribological processes is fundamental to many basic and applied problems, such as wetting, capillarity, adhesion, lubrication, sealing, hardness, micro/nanoindentation, atomic-scale probing, surface modification and manipulation [1][2][3]. The contact of two bodies may be defined by the influential parameters
  • roughness on the contact characteristics we calculated various plasticity indices that have been proposed in the literature. The first here is the one given by the GW model [5][6], (E*/H)(σsks)1/2, where H is the hardness, E* is the reduced Young’s modulus, σs is the surface roughness, and ks is the
  • curvature constant. In the case of the fused silica it was found to be less than unity, whereas both DLC samples feature plasticity indices greater than unity (Table 2). Another modified plasticity index given by the KE model [9] was calculated as (2E*/πKH)(σsks)1/2, where K represents the hardness
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Published 28 Jan 2013

Friction and durability of virgin and damaged skin with and without skin cream treatment using atomic force microscopy

  • Bharat Bhushan,
  • Si Chen and
  • Shirong Ge

Beilstein J. Nanotechnol. 2012, 3, 731–746, doi:10.3762/bjnano.3.83

Graphical Abstract
  • , the maximum indentation displacement was controlled to be 1000 nm [6]. The method for the hardness (H) and the elastic modulus (E) determination was based on established methods [37][38]. Briefly, H was calculated from where Pmax is the maximum imposed load, and A is the projected contact area. The
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Published 08 Nov 2012

Nanotribology at high temperatures

  • Saurav Goel,
  • Alexander Stukowski,
  • Gaurav Goel,
  • Xichun Luo and
  • Robert L. Reuben

Beilstein J. Nanotechnol. 2012, 3, 586–588, doi:10.3762/bjnano.3.68

Graphical Abstract
  • are available for a tool tip for nanotribological applications at elevated temperatures, if not diamond. We attempt to answer this question below. Discussion Principally, ultra-hard materials – materials whose hardness is attributable to covalent bonding – can be represented using the “composition
  • cycle” shown in Figure 1. This cycle involves the four elements carbon (C), boron (B), silicon (Si) and nitrogen (N). The combination of any two chemical species from this composition cycle produces a compound exhibiting ultra-high hardness, e.g., CBN, SiC, Si3N4, B4C and the recently recognized C3N4
  • materials from this composition cycle, diamond (C) and cubic boron nitride (CBN), possess ultra-high hardness (attributed both to sp3-bonding and relatively short bond lengths) and, for this reason, they are frequently used to manufacture cutting tips. While diamond resides in a cubic lattice structure, CBN
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Published 15 Aug 2012

Formation of SiC nanoparticles in an atmospheric microwave plasma

  • Martin Vennekamp,
  • Ingolf Bauer,
  • Matthias Groh,
  • Evgeni Sperling,
  • Susanne Ueberlein,
  • Maksym Myndyk,
  • Gerrit Mäder and
  • Stefan Kaskel

Beilstein J. Nanotechnol. 2011, 2, 665–673, doi:10.3762/bjnano.2.71

Graphical Abstract
  • high mechanical toughness at evaluated temperatures, and the extreme hardness and chemical resistance of SiC, it is often used as welding flux. Phase separation during the welding process is a major technical challenge, and using nanosized particles may help to overcome this problem. So far, no
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Published 07 Oct 2011

Ceria/silicon carbide core–shell materials prepared by miniemulsion technique

  • Lars Borchardt,
  • Martin Oschatz,
  • Robert Frind,
  • Emanuel Kockrick,
  • Martin R. Lohe,
  • Christoph P. Hauser,
  • Clemens K. Weiss,
  • Katharina Landfester,
  • Bernd Büchner and
  • Stefan Kaskel

Beilstein J. Nanotechnol. 2011, 2, 638–644, doi:10.3762/bjnano.2.67

Graphical Abstract
  • . Important requirements concerning these materials are chemical inertness and temperature stability. A material with high temperature stability, as well as excellent heat conductivity, hardness and mechanical stability is SiC [18]. Next to bulk SiC, also composites [19], porous [20][21][22][23][24][25], and
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Published 27 Sep 2011

Infrared receptors in pyrophilous (“fire loving”) insects as model for new un-cooled infrared sensors

  • David Klocke,
  • Anke Schmitz,
  • Helmut Soltner,
  • Herbert Bousack and
  • Helmut Schmitz

Beilstein J. Nanotechnol. 2011, 2, 186–197, doi:10.3762/bjnano.2.22

Graphical Abstract
  • ][16]. Local testing of different cuticular regions of the Melanophila sensillum with a nanoindenter has revealed that the mechanical properties of the exocuticular shell of the sphere and the mesocuticle of the microfluidic core are different: Modulus as well as hardness of the shell are significantly
  • higher. Interestingly, modulus and hardness of reference mesocuticle outside the IR pit organs is much higher than those of the mesocuticle inside the sphere. This points to a specialization of the material inside the sphere (Figure 2C, Figure 2D). Receptor function Currently, two models of sensillum
  • ). Indentation tests were performed by using a three-sided Berkovich diamond tip with a total included angle of 142.3°. A proper area function was established by indenting in a poly(methyl methacrylate) (PMMA) test specimen with known hardness and modulus. Contact depths range from 250 to 1100 nm. The maximum
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Published 30 Mar 2011

Preparation and characterization of supported magnetic nanoparticles prepared by reverse micelles

  • Ulf Wiedwald,
  • Luyang Han,
  • Johannes Biskupek,
  • Ute Kaiser and
  • Paul Ziemann

Beilstein J. Nanotechnol. 2010, 1, 24–47, doi:10.3762/bjnano.1.5

Graphical Abstract
  • Pt segregation is probably overcompensated by the energy needed to form Fe3Pt from FePt. 2.4 Structure of FePt nanoparticles Since the magnetic hardness of FePt alloys strongly depends on the chemical order parameter, we investigated the structure of individual particles by aberration corrected HRTEM
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Published 22 Nov 2010
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