Abstract: Cold working performed before an aging treatment has a significant effect on size and amount of precipitate produced. This could be caused by the increase in defect density, such as vacancies and dislocations. In this research, the Al-Cu-Si alloy was solution-treated, wear-tested and then artificially aged for a period of 1–5 h. Changes in the amount of precipitate, in the lattice par...

In automation flexible manufacturing systems, tool wear detection during the cutting process is one of the most important considerations. This study presents an intelligent system for online tool condition monitoring in drilling process .In this paper, analytical and empirical models have been used to predict the thrust and cutting forces on the lip and chisel edges of a new drill. Also an empi...

To study the tribological performance of metal-on-metal hip joint resurfacings, the wear performance of three pairs of Co-Cr-Mo alloy samples (pins and plates) were tested in a multidirectional pin-on-plate wear machine. An 'as-cast', a single-heat-treated, and a double-heat-treated set of specimens were tested to 3 x 10(6) cycles. The two heat treatments resulted in partial and full solution o...

Many designs of unicompartmental knee replacement show early and mid-term failure due to polyethylene wear. We studied the wear rate of congruent polyethylene meniscal bearings retrieved from failed Oxford unicompartmental knee replacements. We examined 16 bearings, 0.8 to 12.8 years after implantation, measuring their thickness and comparing it with that of 14 unused bearings. The mean rate of...

STUDY DESIGN This is a retrospective study comparing polyethylene wear between ceramic ball heads and metal ball heads in total hip arthroplasty. BACKGROUND The ceramic-on-polyethylene bearing option has been introduced as an alternative to metal-on-polyethylene to minimize polyethylene wear debris and reduce subsequent osteolysis and aseptic loosening. However, the reported data were debatab...

We examined radiographic polyethylene wear in 233 cemented total hip arthroplasties (201 patients) with either a metal-backed or a non-metal-backed acetabular cup. All patients had identical cemented one-piece titanium femoral stems with a femoral head diameter of 28 mm. The mean linear wear rate was 0.11 mm/yr in metal-backed sockets and 0.08 mm/yr in non-metal-backed sockets (p = 0.0002). The...

In rock drilling, bit wear is a major factor in determining bit life, the cost of drilling and may significantly influence the drilling method selected for given rock type. Effective control of bit wear can yield significant cost savings. Prediction of cuttability or drillability requires an understanding of the cutting action and the mode of wear and their interaction with the rock propertiesW...

In this study, we explore the wear behavior of amplitude modulation atomic force microscopy (AM-AFM, an intermittent-contact AFM mode) tips coated with a common type of diamond-like carbon, amorphous hydrogenated carbon (a-C:H), when scanned against an ultra-nanocrystalline diamond (UNCD) sample both experimentally and through molecular dynamics (MD) simulations. Finite element analysis is util...

The Oxford unicompartmental knee replacement (UKR) was designed to minimise wear utilising a fully-congruent, mobile, polyethylene bearing. Wear of polyethylene is a significant cause of revision surgery in UKR in the first decade, and the incidence increases in the second decade. Our study used model-based radiostereometric analysis to measure the combined wear of the upper and lower bearing s...