Nanotribological behavior of deep cryogenically treated martensitic stainless steel

• Germán Prieto,
• Konstantinos D. Bakoglidis,
• Walter R. Tuckart and
• Esteban Broitman

Beilstein J. Nanotechnol. 2017, 8, 1760–1768, doi:10.3762/bjnano.8.177

• nitrogen for 2 h and annealed. The elastic–plastic parameters of the materials were assessed by nanoindentation tests under displacement control, while the friction behavior and wear rate were evaluated by a nanoscratch testing methodology that it is used for the first time in steels. It was found that

• cryogenic treatments increased both hardness and elastic limit of a low-carbon martensitic stainless steel, while its tribological performance was enhanced marginally. Keywords: carbide refinement; cryogenic treatments; friction; nanoindentation; nanoscratch; wear-resistance improvement; Introduction AISI

• martensitic matrix [10]. This carbide refinement improved the macroscale wear resistance of the material by 35% under lubricated and by 90% under dry sliding conditions compared to the conventionally treated specimens [11]. A slight reduction in the macroscale friction coefficient has also been observed [11

The effect of the electrical double layer on hydrodynamic lubrication: a non-monotonic trend with increasing zeta potential

• Dalei Jing,
• Yunlu Pan and
• Xiaoming Wang

Beilstein J. Nanotechnol. 2017, 8, 1515–1522, doi:10.3762/bjnano.8.152

• reduce friction and wear. With respect to fluid lubrication, it can be divided into various regimes or states based on the thickness of the lubricant film, such as dry friction with a lubricant film thickness of ≈1–10 nm, boundary lubrication (≈1–50 nm), thin film lubrication (≈10–100 nm) and fluid film

Development of a nitrogen-doped 2D material for tribological applications in the boundary-lubrication regime

• Shende Rashmi Chandrabhan,
• Velayudhanpillai Jayan,
• Somendra Singh Parihar and
• Sundara Ramaprabhu

Beilstein J. Nanotechnol. 2017, 8, 1476–1483, doi:10.3762/bjnano.8.147

• spectroscopy. N-rGO-based nanolubricants are prepared and their tribological properties are studied using a four-ball tester. The nanolubricants show excellent stability over a period of six months and a significant decrease in coefficient of friction (25%) for small amounts of N-rGO (3 mg/L). The improvement

• nanolubricant in an induced draft (ID) fan results in the remarkable decrease in the power consumption. Keywords: friction; lubrication; nanolubricant; nitrogen-doped reduced graphene oxide; tribology; wear; Introduction Advances in machine technology necessitate the reduction in energy loss by improving the

• tribological performance. This energy loss is caused primarily by friction and wear. The employment of lubricants in machines reduces friction and wear, which results in energy saving. However, the tribological performance of conventional lubricants (water and oil) fails to meet the demand of newly developed

Measuring adhesion on rough surfaces using atomic force microscopy with a liquid probe

• Juan V. Escobar,
• Cristina Garza and
• Rolando Castillo

Beilstein J. Nanotechnol. 2017, 8, 813–825, doi:10.3762/bjnano.8.84

• two solid surfaces (force of adhesion per unit area) that governs contact stresses and strongly influences friction. In such method, the force, Fadh, required to separate a tip from a flat solid sample is measured. Subsequently, a single-asperity continuum contact mechanics model is used to extract

Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy

• Hanaul Noh,
• Alfredo J. Diaz and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 579–589, doi:10.3762/bjnano.8.62

• treatment, this is not as practical since the lateral friction force is not controlled, so that the contact-mode treatment sometimes leaves broken leftovers around the area of interest (see Figure S8, Supporting Information File 1) and can damage the sample. On the origin of the surface aggregates The

The longstanding challenge of the nanocrystallization of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX)

• Florent Pessina and
• Denis Spitzer

Beilstein J. Nanotechnol. 2017, 8, 452–466, doi:10.3762/bjnano.8.49

• towards initiation by friction and electrostatic discharge for nanostructured 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) crystallized by spray flash evaporation (SFE), compared to the raw material (Table 1). The noticeably lower sensitivity towards friction can be based on the self-lubricating effect, as

• n-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (n-CL-20), which was less sensitive towards friction, impact and electrostatic discharge (Table 3). Klapötke has often experienced the influence of particle size on ESD, when stating for example ”the finer the powder of a particular (note

• impact and friction was reduced by two times, therefore questioning the reactivity. Nevertheless, further efforts were made to replace the bacterial cellulose with an energetic matrix. Crystallization in solution allows the formation of large crystals by growth, thus allowing more parametric studies

Biological and biomimetic materials and surfaces

• Stanislav Gorb and
• Thomas Speck

Beilstein J. Nanotechnol. 2017, 8, 403–407, doi:10.3762/bjnano.8.42

• -structured, flexible, hairy structures on their outer surfaces which can trap an air layer under water for time spans of several minutes, days and even months. The biological importance of these air layers may be buoyancy, insulation, oxygen supply during diving and/or friction reduction during swimming and

• diving. The main interest in biomimetic products lies in the potential friction reduction and in antifouling properties. For example, this could be practically implemented by covering the underwater parts of ship hulls with Salvinia effect coatings. Ongoing projects with ship builders aim to realize this

Studying friction while playing the violin: exploring the stick–slip phenomenon

• Santiago Casado

Beilstein J. Nanotechnol. 2017, 8, 159–166, doi:10.3762/bjnano.8.16

• Santiago Casado Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanoscience), Faraday 9, Ciudad Universitaria de Cantoblanco, 28049 Madrid, Spain 10.3762/bjnano.8.16 Abstract Controlling the stick–slip friction phenomenon is of major importance for many familiar situations. This

• the case of a musical bow-stringed instrument, stick–slip is controlled in order to provide well-tuned notes at different intensities. A trained ear is able to distinguish slight sound variations caused by small friction differences. Hence, a violin can be regarded as a perfect benchmark to explore

• bow hairs, suggesting that a structure having peaks and a roughness similar to that of the string to which both bow hairs rubbed permits a better control of the stick–slip phenomenon. Keywords: atomic force microscopy; bow hair; friction; stick–slip; tribology; violin; Introduction Friction is

Structural and tribometric characterization of biomimetically inspired synthetic "insect adhesives"

• Matthias W. Speidel,
• Malte Kleemeier,
• Andreas Hartwig,
• Klaus Rischka,
• Angelika Ellermann,
• Rolf Daniels and
• Oliver Betz

Beilstein J. Nanotechnol. 2017, 8, 45–63, doi:10.3762/bjnano.8.6

• adhesivenesses, ranging between 1–18 mN. The adhesive performance was drastically reduced in the emulsions that contained albumin as the protein component or that lacked protein. Tribometric shear tests were performed at moderate normal loads. Our measured friction forces (4–93 mN in the first and 0.1–5.8 mN in

• able to mimic certain rheological and tribological properties of natural tarsal insect adhesives. Keywords: adhesion; bionics; emulsion; friction; insects; Introduction During evolution, insects have developed the ability to move vertically and upside-down on various kinds of surface, a feat that has

• by the adhesive secretion [7][8][9][10][11][12]. Recently, the suggestion has been made, that during friction regimes, insect adhesives induce rate-dependent viscosity changes caused by non-Newtonian shear strains [5][13][14]. Chemical analyses of adhesive insect secretions employed during locomotion

When the going gets rough – studying the effect of surface roughness on the adhesive abilities of tree frogs

• Niall Crawford,
• Thomas Endlein,
• Jonathan T. Pham,
• Mathis Riehle and
• W. Jon P. Barnes

Beilstein J. Nanotechnol. 2016, 7, 2116–2131, doi:10.3762/bjnano.7.201

• experiments where the conformation of the pad to individual asperities was examined microscopically, our calculations indicate that the pad epithelium has a low elastic modulus, making it highly deformable. Keywords: adhesion; friction; Litoria caerulea; roughness; tree frog; Introduction Tree frogs exhibit

• capillary and viscosity forces between the pad and the surface [1][2][3]. The polygonal epithelial cells (approx. 10 µm in diameter) are covered with nanostructures, which are thought to create friction by direct contact with the surface [3]. The combination of the fluid filled adhesive area and the

• the body. However, as the angle of the board increased, frogs would typically spread their limbs in order to help stay attached. This behaviour (which has been described in previous studies and is not unique to this experiment) helps in producing friction forces whilst keeping the peel angle of the

“Sticky invasion” – the physical properties of Plantago lanceolata L. seed mucilage

• Agnieszka Kreitschitz,
• Alexander Kovalev and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1918–1927, doi:10.3762/bjnano.7.183

• envelope that also influence the dispersal of seeds. To determine the physical properties of Plantago lanceolata seed mucilage we studied (1) composition, (2) desiccation, (3) adhesion, and (4) friction properties of the mucilage under different hydration conditions. We revealed the presence of cellulose

• mucilage against loss from the seed surface. Keywords: adhesion; cellulose mucilage; desiccation; friction; Plantago lanceolata; Introduction The ability of seeds and fruits (diaspores) to form mucilage after hydration is known as myxospermy [1][2]. The mucilaginous diaspores are particularly

• during the measurements, using a binocular microscope equipped with a video camera (KODAK) with coaxial illumination. Friction measurements of the mucilage A series of five measurements, each based on an individual seed set consisting of five seeds, was made. Five seeds were attached to the tilting

Deformation-driven catalysis of nanocrystallization in amorphous Al alloys

• Rainer J. Hebert,
• John H. Perepezko,
• Harald Rösner and
• Gerhard Wilde

Beilstein J. Nanotechnol. 2016, 7, 1428–1433, doi:10.3762/bjnano.7.134

• regions in the matrix adjacent to the shear bands are affected by the deformation [51]. It is also in line with measurements of internal friction in a bulk metallic glass, where early irreversible events upon cyclic straining have been observed at strain levels lower than 0.001. In that study, it was also

Influence of ambient humidity on the attachment ability of ladybird beetles (Coccinella septempunctata)

• Lars Heepe,
• Jonas O. Wolff and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1322–1329, doi:10.3762/bjnano.7.123

• not only dry adhesive setae are affected by ambient humidity, but also setae that stick due to the capillarity of an oily secretion. Keywords: adhesion; beetle; biomechanics; force measurement; friction; insect; locomotion; surface; Introduction Substrate attachment plays an important role in the

• niche occupation of plant-dwelling insects, since it is substantial for resting and locomotion in a complex environment. Consequently, a high diversity of friction and adhesion enhancing structures has evolved among insects [1][2]. Several studies showed that not only the intrinsic structure of an

• droplets of water that are crucial for the function of the adhesive system [28]. The reduction in traction forces observed in the present study at 99% RH (without visible water condensation) may be explained by a sufficient amount of adsorbed water on the substrate. It has been shown that the friction

The self-similarity theory of high pressure torsion

• Yan Beygelzimer,
• Roman Kulagin,
• Laszlo S. Toth and
• Yulia Ivanisenko

Beilstein J. Nanotechnol. 2016, 7, 1267–1277, doi:10.3762/bjnano.7.117

• exponent of a power hardening law). We conclude that if the hardening law is a power law in a rotation interval β, self-similar regimes can emerge in HPT if the friction with the lateral wall of the die is not too high. In these intervals a simple mathematical description can be applied based on self

• stress of the material that depends on the von Mises strain: The set of Equations 3–7 is solved under the following boundary conditions: where m is the friction coefficient and ω is the torsion rate of the anvil. Under the terms of Equation 9 we believe there is no slippage in the contact between the

• Equations 32–35. It follows from Equation 39 that if the evolution of the process is self-similar, the torque M(β) during HPT satisfies a power law, i.e.,: If the hardening law does not satisfy a power law form, there is no self-similar solution. When there is no friction on the cylindrical surface of the

Reasons and remedies for the agglomeration of multilayered graphene and carbon nanotubes in polymers

• Rasheed Atif and
• Fawad Inam

Beilstein J. Nanotechnol. 2016, 7, 1174–1196, doi:10.3762/bjnano.7.109

• , the concentration of oxygen on the CNT surface increases, which decreases the contact angle. The lower contact angle results in an improvement of interfacial interactions and leads to an enhancement of mechanical properties such as tensile strength, modulus and coefficient of friction [123]. Eitan et

Advanced atomic force microscopy techniques III

• Thilo Glatzel and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2016, 7, 1052–1054, doi:10.3762/bjnano.7.98

• two major categories: local measurements of mechanical properties and high resolution force measurements and spectroscopy. The characterization of mechanical properties by AFM manifests themselve primarily in the local detection of adhesion, friction and elasticity. Georg Fantner and his co-workers

• several transitions in the friction coefficient with increasing load have been found on Au(111) in sulfuric acid electrolyte containing Cu ions by Helmut Baltruschat an co-workers [24] and the stiffness of micron-sized sphere-plate contacts was studied by Diethelm Johannsmann et al. by employing high

Generalized Hertz model for bimodal nanomechanical mapping

• Aleksander Labuda,
• Marta Kocuń,
• Waiman Meinhold,
• Deron Walters and
• Roger Proksch

Beilstein J. Nanotechnol. 2016, 7, 970–982, doi:10.3762/bjnano.7.89

• ][5], force modulation [6][7], phase imaging [8][9], loss tangent imaging [10], friction force microscopy [11], creep compliance [12], shear modulation force microscopy [13], pulsed force microscopy [14] and torsional approaches [15]. These techniques can be broadly classified as either “parametric

Facile synthesis of water-soluble carbon nano-onions under alkaline conditions

• Gaber Hashem Gaber Ahmed,
• Rosana Badía Laíño,
• Josefa Angela García Calzón and
• Marta Elena Díaz García

Beilstein J. Nanotechnol. 2016, 7, 758–766, doi:10.3762/bjnano.7.67

• found applications as materials for tribology due to their low friction [10]. Polymers doped with C-onions exhibit increased thermal resistance and can be used as microwave absorbing filters due to the C-onions ability to absorb electromagnetic radiation in the 26–37 GHz range [11]. Also, C-onions have

Tight junction between endothelial cells: the interaction between nanoparticles and blood vessels

• Yue Zhang and
• Wan-Xi Yang

Beilstein J. Nanotechnol. 2016, 7, 675–684, doi:10.3762/bjnano.7.60

• material and shows its influence on blood vessels when blood flows in parallel through the vessel. In the field of angiology, shear stress is embodied in the index of endothelial shear stress, which originates from the friction of flowing blood and is proportionally determined by the viscosity of blood and

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• important complimentary information on heterogeneous material systems [9]. By measuring the force on a scanning probe tip as it interacts with the sample, material properties including friction, adhesion, deformation, modulus, and dissipation can be quantified and mapped over nanoscale distances [10][11][12

Charge and heat transport in soft nanosystems in the presence of time-dependent perturbations

• Alberto Nocera,
• Carmine Antonio Perroni,
• Vincenzo Marigliano Ramaglia and
• Vittorio Cataudella

Beilstein J. Nanotechnol. 2016, 7, 439–464, doi:10.3762/bjnano.7.39

• on the Keldysh contour. The semiclassical approach naturally includes the effect of a noise term that stems form the quantum charge fluctuations induced by the fast time scales of the electronic system. The friction and the noise strengths depend by construction on the displacement of the oscillator

• included the effect of the forcing antenna in our adiabatic scheme showing that the resulting Langevin equation for the vibrational mode is modified by a periodic forcing term. Moreover, the generalized force term, the friction and the noise strengths become functions that depend on the oscillator

• -dependent memory-friction kernel of the oscillator [80]. In the regime for all the modes, can be approximated as real and independent of frequency, providing the damping rate . [80] If not specified, we consider the symmetric configuration: γL = γR = γ/2. In this review, we assume that the electronic and

Rigid multipodal platforms for metal surfaces

• Michal Valášek,
• Marcin Lindner and
• Marcel Mayor

Beilstein J. Nanotechnol. 2016, 7, 374–405, doi:10.3762/bjnano.7.34

Molecular machines operating on the nanoscale: from classical to quantum

• Igor Goychuk

Beilstein J. Nanotechnol. 2016, 7, 328–350, doi:10.3762/bjnano.7.31

• considered and discussed to highlight generic physical features. This work examines some common fallacies that continue to plague the literature. In particular, the erroneous beliefs that one should minimize friction and lower the temperature for high performance of Brownian machines, and that the

• ; nanoscale friction and thermal noise; quantum effects; thermodynamic efficiency; Introduction A myriad of minuscule molecular nanomotors (not visible in standard, classical, optical microscopes) operate in living cells and perform various tasks. These utilize metabolic energy, for example, the energy

• . Review Fluctuation–dissipation theorem, the role of thermal fluctuations Motion in any dissipative environment is necessarily related to the dissipation of energy. Particles experience a frictional force, which in the simplest case of Stokes friction is linearly proportional to the particle velocity with

Current-induced runaway vibrations in dehydrogenated graphene nanoribbons

• Rasmus Bjerregaard Christensen,
• Jing-Tao Lü,
• Per Hedegård and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2016, 7, 68–74, doi:10.3762/bjnano.7.8

• to the four forces Here, FR, NC, RN, BP represent the electronic friction, nonconservative force, renormalization of the atomic potential, and Berry-phase-induced pseudo-magnetic force, respectively [12]. Run-away modes In order to analyze the influence of the current we define the nonequilibrium

• frequency-dependent. Thus, to analyze a specific runaway mode giving rise to a negative peak in Figure 2a (see below), we evaluate the self-energy at the negative peak frequency ω0 as given below in Equation 10, Thus, the dynamical matrix is renormalized by and the friction originates from . Solving

Negative differential electrical resistance of a rotational organic nanomotor

• Hatef Sadeghi,
• Sara Sangtarash,
• Qusiy Al-Galiby,
• Rachel Sparks,
• Steven Bailey and
• Colin J. Lambert

Beilstein J. Nanotechnol. 2015, 6, 2332–2337, doi:10.3762/bjnano.6.240

• nanotubes [27][28] with very low interwall friction [29][30][31][32][33][34] lead to novel electrical properties [35][36][37][38][39][40]. These examples illustrate how an electric field can induce motion and also how a motion-induced change of geometry can affect electrical properties. In what follows, our