BACKGROUND Fiber-reinforced polymer composite (FRPC) archwires could provide an esthetic solution to conventional orthodontic archwires. This study was carried out with the following aims: (1) to compare the sliding friction of FRPC archwire with nickel titanium archwire using various archwire-bracket combinations and (2) to determine the correlation between surface roughness and friction of th...

In this research, surface composite layers containing nano sized TiB2, Al2O3-TiB2, ZrO2 and CNT particles have been fabricated on Aluminum alloy substrates by friction stir processing. The effects of different processing variables such as number of passes and strengthening particle distribution, hardness, and wear properties of surface nano...

The microstructure and wear resistance of Stellite 6 alloy hardfacing layer at two different temperatures (room temperature and 300°C) were investigated by plasma arc surfacing processes on Q235 Steel. Tribological test was conducted to characterize the wear property. The microstructure of Stellite 6 alloy coating mainly consists of α-Co and (Cr, Fe)7C3 phases. The friction coefficient of Stell...

Traditional analyses of slip at corners of contacts, based on linear elasticity and a Coulomb friction law, are very sensitive to the details of local geometries, owing to the effects of elastic singularities. Following the use of cohesive-zone models to address such issues in mode-II fracture, we present analyses of slip and wear at corners of contacts when a finite interfacial shear strength ...

Articular cartilage is an example of a highly efficacious water-based, natural lubrication system that is optimized to provide low friction and wear protection at both low and high loads and sliding velocities. One of the secrets of cartilage's superior tribology comes from a unique, multimodal lubrication strategy consisting of both a fluid pressurization mediated lubrication mechanism and a b...

This paper presents a PEEK filled PTFE composite that exhibits low friction and ultra-low wear. It is hypothesized that a synergistic effect shuts down the dominant wear mechanism of each constituent. The friction coefficient and wear rate of this composite material on lapped stainless steel were evaluated for samples with PEEK wt.% of 0, 5, 10, 20, 30, 40, 50, 70 and 100 using a linear recipro...

Advanced carbon dioxide-cooled nuclear reactor environments can be tribologically hostile, with steel components sliding in contact at high temperatures. Although wearprotective oxides can reduce damage in the steady-state conditions, severe wear can occur in the early stages, particularly at temperatures of 300 to 500 "C, where oxidation rates may be low. In this paper, results are presented o...

Owing to larger surface area in micro/nanoelectromechanical systems (MEMS/NEMS), surface forces such as adhesion, friction, and meniscus and viscous drag forces become large when compared with inertial and electromagnetic forces. There is a need to develop lubricants and identify lubrication methods that are suitable for MEMS/NEMS. For BioMEMS/BioNEMS, adhesion between biological molecular laye...