In this article, the measurement of wear i n radial journal bearings is discussed, where a distinction is made between stationa y and non-stationa y contact conditions. Starting with Holm/ArchardS wear law, equations are derived for the calculation of the specific wear rate k of the bearing material as afunction of the wear depth d, measured after an experiment or a period of use i n practice. ...

Abrasive wear is one of the prime and mostly costly causes of secondary failure in the design and operation of mechanical machines and equipment. Wear limits must be known and measured to assure quality and durability of products by an experimental process to determine an optimum material composition. The development of wear monitoring systems for industrial processes is well recognised in the ...

The Oxford Unicompartmental Knee replacement (UKR) was introduced as a design to reduce polyethylene wear. There has been one previous retrieval study involving this implant, which reported very low rates of wear in some specimens but abnormal patterns of wear in others. There has been no further investigation of these abnormal patterns. The bearings were retrieved from 47 patients who had rece...

predation rate is basic to any investigation of prey-predator interaction and a major component in the selection of predators for biological control. the predation rate of variegated lady beetle, hippodamia variegata (goze), fed on different densities (20, 40, 60, 80 and 100) of third instar nymphs of cotton aphid, aphis gossypii glover, was studied under laboratory conditions (25 ± 1 °c, 65 ± ...

purpose: to evaluate the prevalence of contat lens wear among highschool girls and their general knowledge about contact lenses and also to evaluate the specific knowledge of contact lens wearers about the lens. methods: in a cross-sectional study, 1664 students of 22 randomly selected girl highschools were enrolled. a questionaire including questions about wearing contact lens, age of first us...

On time replacement of a cutting tool with a new one is an important task in Flexible Manufacturing Systems (FMS). A fuzzy logic-based approach was used in the present study to predict and simulate the tool wear progress in turning operation. Cutting parameters and cutting forces were considered as the input and the wear rate was regarded as the output data in the fuzzy logic for construct...

The average life span of knee prosthesis used in Total Knee Replacement (TKR) is approximately 10 to 15 years. Literature indicates that the reasons for implant failures include wear, infection, instability, and stiffness. However, the majority of failures are due to wear and tear of the prosthesis. The most common biopolymer used in TKR  is Ultra High Molecular Weight Polyethylene (UHMWPE). Pr...

functionally graded aluminium/zirconia metal matrix composite was fabricated using stir casting technique followed by horizontal centrifugal casting process and a hollow cylindrical functionally graded composite (150 x 150 x 16 mm) was obtained with centrifuging speed of 1200 rpm. the microstructural evaluation and hardness test was carried out on the outer and inner surface of the functionally...

in manufacturing industry, it has been acknowledged that tool wear prediction has an important role in higher quality of products and acceptable efficiency. being an emerging area of research in recent years, drilling tool wear is an important factor which directly affects quality parameters of machined hole such as hole centring, roundness, burr formation and finished surface. in this paper, t...

friction stir processing was applied for fabricating an aluminum alloy based hybrid nano composite reinforced with nano sized al2o3 and micro sized graphite particles. a mixture of al2o3 and graphite particles was packed into a groove with 1 mm width and 4.5 mm depth, which had been cut in 5083 aluminum plate of 10 mm thick. packed groove was subjected to friction stir processing in order to im...