Wear experiments have shown that when the applied normal stress exceeds a critical value, a transition occurs from the regime of mild wear to that of adhesive wear. As a result, the wear rate of particle-reinforced aluminium composites increases by a hundred-fold. Based on dislocation and delamination theories, a criterion is proposed for determining the critical transition load, and a quantita...

We consider fretting wear due to tangential oscillations of two contacting bodies. For small oscillation amplitudes, the wear occurs only in a circular slip zone at the border of the contact area. With increasing number of cycles, the wear profile tends to a limiting form, in which no further wear occurs. Under assumption of a constant coefficient of friction, the limiting form of the wear prof...

OBJECTIVE To classify wear and non-wear time of accelerometer data for accurately quantifying physical activity in public health or population level research. DESIGN A bi-moving-window-based approach was used to combine acceleration and skin temperature data to identify wear and non-wear time events in triaxial accelerometer data that monitor physical activity. SETTING Local residents in Sw...

Femoral components of hip replacements are commonly anchored in the femur with bone cement or poly(methyl methacrylate) (PMMA). Wear or fracture of bone cement can lead to loosening of the femoral component, which drastically affects the success and longevity of hip replacements. Self-reinforced composite PMMA (SRC-PMMA) has been previously developed for potential use, as a precoat material for...

In gears running under conditions of high load and low circumferential speed the lubricant film thickness is often not sufficient to fully separate the mating surfaces. Wear of the gear flanks can occur and can even result in total gear failure. For a given gear geometry the main influencing parameters are load, circumferential speed and lubricant. The wear characteristics of lubricants depend ...

In industrial production systems, including the most important factors in the economic field machining operations, reduce tool wear due to abrasive nature of the phenomenon on many factors, including temperature Lathe tool, influences, machining conditions (cutting speed, speed losses, forcing to rebuild parts of the manufacturing tolerances disassemble tool wear is caused by the phenomenon, as...

The African apes possess thinner enamel than do other hominoids, and a certain amount of dentin exposure may be advantageous in the processing of tough diets eaten by Gorilla. Dental wear (attrition plus abrasion) that erodes the enamel exposes the underlying dentin and creates additional cutting edges at the dentin-enamel junction. Hypothetically, efficiency of food processing increases with j...

STATEMENT OF PROBLEM Colored zirconia is widely used in dental clinical practice; however, data pertaining to its wear resistance after different surface treatments are sparse. PURPOSE The purpose of this in vitro study was to evaluate the 2-body wear resistance of dental colored zirconia after different glazing and polishing treatments. MATERIAL AND METHODS Standardized specimens were prep...

Thermoset and thermoplastic polymeric materials are used as coatings on the bore of downhole tubulars such as water injectors in the oil industry. Previous work has indicated that such coatings can fail by impact damage and by abrasion from the wire used to lower inspection tools down the tubular. The wire is commonly called “slickline” and the type of wear is called “wireline wear”. However, t...

Ultra-high molecular weight polyethylene wear particles have been implicated as the major cause of osteolysis, implant loosening and late aseptic failure in total hip arthroplasties in vivo. This study initially screened 22 carbon-carbon composite materials as alternatives for UHMWPE in joint bearings. New bearing materials should satisfy certain criteria--they should have good wear properties ...