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

• 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

• strength. Lin et al. studied the tribological properties of modified graphene platelets dispersed in oil and shows that the graphene platelets improved the wear resistance and load-carrying capacity of the machine after the modification [22]. Song et al. compared the tribological properties of multiwalled

Functional dependence of resonant harmonics on nanomechanical parameters in dynamic mode atomic force microscopy

• Federico Gramazio,
• Matteo Lorenzoni,
• Francesc Pérez-Murano,
• Enrique Rull Trinidad,
• Urs Staufer and
• Jordi Fraxedas

Beilstein J. Nanotechnol. 2017, 8, 883–891, doi:10.3762/bjnano.8.90

• works, at the sharp attractive–repulsive transition, which implies a rather involved experimental determination, while using approach curves one can select the setpoint and thus the A6 intensity in a larger range (within the repulsive mode). However, larger repulsions may lead to wear, and thus to

• with a higher slope at the beginning and a lower slope afterwards. Because of the expected tip wear, the evolution observed in Figure 5 can be again ascribed to an increase in tip radius. This method has been proposed to monitor the stability of the tip in a continuous manner [13][26][27]. The

• samples have to be changed, a variation of the tip radius cannot be excluded. The sample with the highest wear was titanium, because of its higher roughness as compared to the rest of the samples, and for this reason it was measured at the end of the cycles. From the figure it can be clearly observed that

Diffusion and surface alloying of gradient nanostructured metals

• Zhenbo Wang and
• Ke Lu

Beilstein J. Nanotechnol. 2017, 8, 547–560, doi:10.3762/bjnano.8.59

• and alloys. In addition, GNS materials exhibit significantly enhanced wear resistance and fatigue resistance compared with their nano-grained and CG counterparts [4][5][6][7]. Investigating the diffusion behavior of GNS materials is an important topic mostly due to the following reasons: Numerous

• works have been carried out on advancing surface alloying techniques of metals with a preformed nanostructured surface layer. The advantages are distinct, for example, improving surface properties such as wear and corrosion resistance with higher energy/time efficiency, reducing work-piece distortion

• -temperature processes: Surface alloying processes, such as nitriding and aluminizing, have been achieved on various engineering metals with a GNS surface layer at temperatures much lower than the conventional processing temperatures, and properties such as resistance to wear and corrosion were significantly

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

• , earthquakes, the squeaky sounds caused by the scratching of two surfaces like a chalk on a blackboard, the grinding of a rusty hinge, or the wear of articular joints [4]. This phenomenon is caused by the rupture of equilibrium occurring when two materials are steadily being rubbed against each other

Functional diversity of resilin in Arthropoda

• Jan Michels,
• Esther Appel and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1241–1259, doi:10.3762/bjnano.7.115

• break) in the wings of wasps plays a major role in mitigating wing wear by flexion along this joint when the wings hit an obstacle. This mechanism is especially important for wings with wing veins extending all the way to the tip because such a design endows a wing with more spanwise rigidity than, for

In situ observation of deformation processes in nanocrystalline face-centered cubic metals

• Aaron Kobler,
• Christian Brandl,
• Horst Hahn and
• Christian Kübel

Beilstein J. Nanotechnol. 2016, 7, 572–580, doi:10.3762/bjnano.7.50

• materials [24], radiation-resistant materials for nuclear reactors [25], applications for wear and corrosion protection [6][26] and for flexible electrical components [27]. Beside simulations [12][13][14][17][28][29], only few experimental methods are capable to measure in situ structural signatures of the

Sonochemical co-deposition of antibacterial nanoparticles and dyes on textiles

• Ilana Perelshtein,
• Anat Lipovsky,
• Nina Perkas,
• Tzanko Tzanov and
• Aharon Gedanken

Beilstein J. Nanotechnol. 2016, 7, 1–8, doi:10.3762/bjnano.7.1

• uses, military clothing, work-wear uniform, and as household decorative textiles. XRD patterns of sonochemically coated fabrics with: (a) ZnO and (b) CuO NPs. Images of textile fibers (shredded bandages) colored with RO16 and RB5 dyes and functionalized with ZnO and CuO NPs in a one-step sonochemical

Nanoscale rippling on polymer surfaces induced by AFM manipulation

• Mario D’Acunto,
• Franco Dinelli and
• Pasqualantonio Pingue

Beilstein J. Nanotechnol. 2015, 6, 2278–2289, doi:10.3762/bjnano.6.234

• wide spectrum of polymers has been investigated including polystyrene (PS) [13][20], poly(methyl methacrylate) (PMMA) [25], poly(ethylene terephthalate) (PET) [23], poly(vinyl acetate) (PVAc) [26] and poly(ε-caprolactone) (PCL) [23]. Recently, we have reviewed wear occurring on polymeric surfaces and

• well known before the invention of the AFM methods. In particular, it was studied at a macroscopic level by sliding stiff objects, generally cones or spheres, over polymer samples. Plastic deformation and wear of polymer surfaces represented the subject of several experimental works carried out

• starting from the sixties of the last century. One of the most striking observations was the formation of macroscopic surface undulations, nowadays known as ‘Schallamach waves’ [28][29]. With the invention of AFM, the scientific interest moved to the investigation of plastic deformation and wear in polymer

Lower nanometer-scale size limit for the deformation of a metallic glass by shear transformations revealed by quantitative AFM indentation

• Arnaud Caron and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2015, 6, 1721–1732, doi:10.3762/bjnano.6.176

• highly concentrated around the AFM indenter. In a recent study, we have compared the nano-scale wear of Pt(111) and Pt57.5Cu14.7Ni5.3P22.5 metallic glass by AFM scratching in UHV. The friction forces measured during reciprocal scratching with a diamond-coated silicon tip were found to be four times

Stiffness of sphere–plate contacts at MHz frequencies: dependence on normal load, oscillation amplitude, and ambient medium

• Jana Vlachová,
• Rebekka König and
• Diethelm Johannsmann

Beilstein J. Nanotechnol. 2015, 6, 845–856, doi:10.3762/bjnano.6.87

• fretting wear [1][2] granular media [3], earthquakes [4], and the collision between particles [5]. Early models of partial slip were formulated independently by Cattaneo [6] and Mindlin [7], who were concerned with a Hertzian contact. If the entire contact area sticks, a continuum treatment predicts a

• small tangential displacement at contacts between rough surfaces. These small displacements per se have little influence on the strength of the contact. They are still of immense practical relevance because they cause fretting wear [19][20][21], which is a special type of corrosion. Microslip at

• crack tip. The load dependence of µ points to yet another benefit of “contact splitting” [40][41]. A large number of small contacts will experience less partial slip (less fretting wear) than a small number of correspondingly larger contacts. A side remark: The agreement between the two friction

Stick–slip behaviour on Au(111) with adsorption of copper and sulfate

• Nikolay Podgaynyy,
• Sabine Wezisla,
• Christoph Molls,
• Shahid Iqbal and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2015, 6, 820–830, doi:10.3762/bjnano.6.85

• . The slope of the stick curve is 12 N/m. In all cases it is between 10 and 12 N/m and independent of potential. It is important to mention that at all potentials the surface is very resistant to wear; even at high normal loads of about 250 nN, atomic resolution is always visible. At the pzc the quality

Mapping of elasticity and damping in an α + β titanium alloy through atomic force acoustic microscopy

• M. Kalyan Phani,
• Anish Kumar,
• T. Jayakumar,
• Walter Arnold and
• Konrad Samwer

Beilstein J. Nanotechnol. 2015, 6, 767–776, doi:10.3762/bjnano.6.79

• the global ultrasonic absorption is obtained at higher loads only. Hence, a slightly higher value of load was selected at which no noticeable wear of the tip and no slipping in the tip–sample contact were observed and, hence, uniform measurements throughout the scan were assured. The contact-resonance

Mandibular gnathobases of marine planktonic copepods – feeding tools with complex micro- and nanoscale composite architectures

• Jan Michels and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2015, 6, 674–685, doi:10.3762/bjnano.6.68

• break because of local stress concentrations under high mechanical loads when they are in contact with other hard structures [44]. To test the idea that the non-siliceous gnathobase parts might have evolved specific properties that reduce the risk of wear and damage of the siliceous teeth, the materials

• gradient in the material properties) can make these systems more resistant to damage and wear because such an architecture minimises the probability of local stress concentrations and, in the case of an initial damage, prevents further crack propagation [47][48]. It is conceivable that the soft and elastic

Boosting the local anodic oxidation of silicon through carbon nanofiber atomic force microscopy probes

• Gemma Rius,
• Matteo Lorenzoni,
• Soichiro Matsui,
• Masaki Tanemura and
• Francesc Perez-Murano

Beilstein J. Nanotechnol. 2015, 6, 215–222, doi:10.3762/bjnano.6.20

• present paper. As far as the tips did not make contact with the surface (either by particle contamination or the surface or problems with feedback loop control) we did not observe tip wear. Discussion In Figure 6 the main results of the kinetics study of LAO-AFM are summarized. Figure 6a shows the line

Multifunctional layered magnetic composites

• Maria Siglreitmeier,
• Baohu Wu,
• Tina Kollmann,
• Martin Neubauer,
• Gergely Nagy,
• Dietmar Schwahn,
• Vitaliy Pipich,
• Damien Faivre,
• Dirk Zahn,
• Andreas Fery and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2015, 6, 134–148, doi:10.3762/bjnano.6.13

• ]. Chitons scratch algae from rocks, which requires wear-resistant teeth. The animal maintains this ability by synthesizing rows of teeth and each time, a tooth is worn out, the next tooth in the row will be used. A reason for the mechanical wear resistance of the teeth is the presence of different iron

• future mechanical measurements will show in how far the fracture resistance of nacre could be combined with the wear resistance of chiton teeth. Experimental Chemicals The following commercially available chemicals were purchased and applied in the syntheses without further purification: FeCl2·4H2O

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• compared to HA alone, an increase in elasticity of up to 120%, a 129% increase in hardness, and an 86% increase in fracture toughness were possible. The BNNT–HA composite also showed a 75% increase in the wear resistance. It was noted that the addition of BNNTs to HA did not have any adverse effect on

Modeling viscoelasticity through spring–dashpot models in intermittent-contact atomic force microscopy

• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2014, 5, 2149–2163, doi:10.3762/bjnano.5.224

• dynamic method and has been the subject of thorough studies [2][3][4][5][6]. In tapping mode AFM damage or wear of the tip and surface are reduced with respect to contact-mode AFM due to lower friction and lateral forces, which makes it more applicable for imaging soft samples, such as polymers and

Carbon nano-onions (multi-layer fullerenes): chemistry and applications

• Juergen Bartelmess and
• Silvia Giordani

Beilstein J. Nanotechnol. 2014, 5, 1980–1998, doi:10.3762/bjnano.5.207

• widely studied and have shown promising results as lubricants. In 2002, Cabioc’h et al. reported that CNOs incorporated in silver layers significantly reduced wear, while the friction coefficient is largely unaffected by their presence [74]. Further studies investigated the use of CNOs as a solid state

• ][78][79][80]. Mechanisms by which CNOs can reduce friction and wear were investigated in greater detail in 2009 by Martin and collaborators in a combined experimental and computational study [81]. Computer simulations suggest that the lubrication of CNOs between two surfaces is caused by rolling

• –sliding of the CNO nanoparticles. These findings were corroborated by TEM observations of the wear particles and AFM imaging of the wear tracks. Optical limiting CNOs were also studied in optics and found to exhibit very efficient optical limiting [82]. Furthermore, the authors of this study compared the

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• , Friedrich-Loeffler-Institut, Höltystr. 10, 31535 Neustadt, Germany 10.3762/bjnano.5.165 Abstract Due to the abundance of nanomaterials in medical devices and everyday products, toxicological effects related to nanoparticles released from these materials, e.g., by mechanical wear, are a growing matter of

• , mammalian cells and bacteria are considered. Keywords: albumin; gold-silver; implant alloy; laser ablation; nickel-titanium; size control; wear debris; Introduction The widespread use of medical implants consisting of metals (e.g., gold coatings [1]) and alloys (e.g., NiTi, CoCr, stainless steel) [2][3][4

• nanoscopic wear debris [6][7][8] which have been reported to accumulate in lymph nodes, bone marrow, liver and spleen [9]. In that context toxicological effects, including impaired DNA replication and cell growth as well as inflammatory responses, are meant to originate from release of toxic heavy metal ions

Dry friction of microstructured polymer surfaces inspired by snake skin

• Martina J. Baum,
• Lars Heepe,
• Elena Fadeeva and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 1091–1103, doi:10.3762/bjnano.5.122

• lead to a stronger abrasive wear on the tribo-pair. Nevertheless by such kind of surface modification, they were able to reduce the frictional coefficient. A comparison of these finding with the results of our study is only possible in a limited way, because they used for their investigation a

• that a decrease in frictional coefficient is due to the reduction of adhesive components of the frictional mechanisms [51][52]. Another approach to explain the reduction in frictional coefficient on many microstructured surfaces could be the possibility of trapping of loose wear particles within the

• microstructures and thereby the avoidance of further surface ploughing by these wear particles [38][48][50][53]. The gap between biologically and artificially microstructured surfaces can be closed by interpreting the microstructure of the SIMPS as lines and spaces, in which the lines are periodically interrupted

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

• PDMS, kapton/polycarbonate, Si/SiO2. Furthermore, when PDMS is applied as an intermediate layer between a harder substrate and titania, marked improvement in the scratch resistance is achieved. This is shown by quantitative wear tests for silicon or kapton, by coating these substrates with PDMS which

• is subsequently capped by a titania layer, resulting in enhanced scratch/wear resistance. The physical basis of this effect is explored by means of Finite Element Analysis, and we suggest a model for friction reduction based on the "cushioning effect” of a soft intermediate layer. Keywords: finite

• also give substantial improvement in the wear and friction behavior [2]. A third approach, which has the major advantage of not changing the bulk polymer properties is to use inorganic coatings [9][10]. One such attempt to reduce sensitivity to scratching involves depositing an oxide coating on the

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

• important for reduced friction and wear. Figure 9 shows examples of load–displacement curves at intermediate and high loads (left) along with topography maps of the nanoparticles over a 10 µm × 10 µm scan area and 2-D profiles before and after indentation (right). The intermediate and high loads were 500

• ). Compression tests, as well as indentation tests, simulate the types of contacts nanoparticles encounter during different friction and wear conditions. For this purpose, a tip approximately 3.5 µm in radius was used to carry out compression tests. Figure 10 shows a typical load displacement curve for

Friction behavior of a microstructured polymer surface inspired by snake skin

• Martina J. Baum,
• Lars Heepe and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2014, 5, 83–97, doi:10.3762/bjnano.5.8

• adaptation to reduce wear. Based on this extensive comparative study of different microstructured polymer samples, it was experimentally demonstrated that the friction-induced stick-slip behavior does not solely depend on the frictional coefficient of the contact pair. Keywords: fast Fourier transformation

• strongly depend on material properties of the sliding partners, the optimal stick-slip reducing dimension of microstructures must be engineered for every single technical application. Nevertheless, it could be a very effective way to reduce frictional energy loss and friction-induced wear. In the present

• optimization [17], reduction of wear rate [35] and as shown in our study at hand reduction in stick-slip motion with it. The reduction of stick-slip behavior is directly related to the reduction of wear. Additionally, "controlled" stick-slip motion compared to "uncontrolled", randomly appearing stick-slip

Reversible mechano-electrochemical writing of metallic nanostructures with the tip of an atomic force microscope

• Christian Obermair,
• Marina Kress,
• Andreas Wagner and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2012, 3, 824–830, doi:10.3762/bjnano.3.92

• nanolithography, the results also help in understanding microscopic mechanisms of mechanically activated or mechanically assisted electrochemical processes on metallic surfaces, e.g., during electropolishing or in combined mechanical wear and corrosion processes. Experimental The experimental setup was described