Natural contacting surfaces have remarkable surface mechanical properties, which has led to the development of bioinspired surface structures using rubbery materials with strongly enhanced adhesion and static friction. However, sliding friction of structured rubbery surfaces is almost always significantly lower than that of a flat control, often due to significant loss of contact. Here we show ...

Transition metal nitrides like CrN and TiN are widely used in automotive applications due to their high hardness and wear resistance. Recently, we showed that a multilayer architecture of CrN and TiN, deposited using the hybrid-high power impulse magnetron sputtering (HIPIMS) and direct current magnetron sputtering (DCMS)-HIPIMS/DCMS deposition technique, results in coatings which indicate not ...

OBJECTIVE To compare the influence of archwire material (NiTi, beta-Ti and stainless steel) and brackets design (self-ligating and conventional) on the frictional force resistance. MATERIAL AND METHODS Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brackets - Gemini, 3M/Unitek) with three (0, 5, and 10 degrees) slot angulation attached with elastomeric...

Introduction: The present study aimed to evaluate an experimental herbal mouthwash, as compared to sodium fluoride mouthwash on the frictional resistance and surface roughness between brackets and two rectangular archwire types. Methods: A total of 60 premolar׳s brackets engaged with 0.019×0.025 archwires made of stainless steel and nickel-titanium alloys were used in this study. The samples we...

To lower the friction coefficient and increase the wear resistance of epoxy, nanoparticles of zinc oxide and polytetrafluoroethylene (PTFE) were added in small volume percents to an epoxy matrix. Tribological testing of the samples in this study was completed on a linear reciprocating tribometer with a 250 N normal load and a 50.8 mm/s sliding speed. Several samples were made and tested followi...

The friction and wear properties of graphene and graphene oxide (GO) with varying C/O ratio were investigated using friction force microscopy. When applied as solid lubricants between a sliding contact of a silicon (Si) tip and a SiO2/Si substrate, graphene and ultrathin GO films (as thin as 1-2 atomic layers) were found to reduce friction by ∼6 times and ∼2 times respectively as compared to th...

To clarify the friction durability, both during and after the high-temperature heating of nanometer-thick diamond-like carbon (DLC) films, deposited using filtered cathodic vacuum arc (FCVA) and plasma chemical vapor deposition (P-CVD) methods, the dependence of the friction coefficient on the load and sliding cycles of the DLC films, were evaluated. Cluster-I consisted of a low friction area i...

This paper reports on a tactile sensor using piezoresistive beams for detection of the coefficient of static friction merely by pressing the sensor against an object. The sensor chip is composed of three pairs of piezoresistive beams arranged in parallel and embedded in an elastomer; this sensor is able to measure the vertical and lateral strains of the elastomer. The coefficient of static fric...

background: friction is usually encountered during sliding technique for orthodontic space closure. this study aims to investigate the effect of fluoride on frictional resistance between stainless steel orthodontic brackets and steel and niti arch wires. materials and methods: a total of 144 standard 022 stainless steel brackets were used in this experimental study. 0.016 and 0.019 × 0.025 inch...

Frictional interfaces abound in natural and man-made systems, yet their dynamics are not well-understood. Recent extensive experimental data have revealed that velocity-strengthening friction, where the steady-state frictional resistance increases with sliding velocity over some range, is a generic feature of such interfaces. This physical behavior has very recently been linked to slow stick-sl...