statement of problem: as a physical property, wear resistance of the materials used in the fabrication of orthodontic retainers play a significant role in the stability and long term use of the appliances. objectives: to evaluate the wear resistance of two commonly used materials for orthodontic retainers: acropars op, i.e. a polymethyl methacrylate based material, and 3a-gs060, i.e. a polyethy...

The characteristics of the cutting forces were studied at different usage levels and the analytical model of the micro-end-milling operations was modified to represent the tool wear. A new expression was derived from the model to estimate the remaining tool life from experimental data. The parameters of the model are estimated by using genetic algorithms. The difference between the simulated an...

A wear prediction model is built to research the of curved switch rail in a high-speed turnout. The Archard used analyze profile evolution law. non-Hertzian contact Kik–Piotrowski method based on virtual penetration as algorithm for model. dynamic vehicle–curved system predicted profiles and measured wheel with different stages established. effect profiles’ vehicle performance analyzed. results...

Metal matrix composites (MMCs) are now gaining their usage in aerospace, automotive and biomedical industries because of their inherent properties like high strength to weight ratio, low wear rate etc. To machine these types of materials conventional machining methods are unsuitable because of high tool wear and tooling cost. Electro discharge Machining (EDM) is one of the important nontraditio...

Abstract The development of numerical models able to compute the wheel and rail profile wear is essential improve scheduling maintenance operations required restore original shapes. This work surveys main in literature for evaluation uniform profiles. standard structure these tools includes a multibody simulation wheel–track coupled dynamics module implementing an experimental law. Therefore, a...

aa8090 is an extra light and deformable group of lithium containing aluminum alloys which have recently replaced some aerospace aluminum alloys, such as 2000 and 7000 series, due to their higher elastic modulus and lower specific weight. in this study, aa8090 matrix composites containing 3, 6 and 9 vol.% sic were cast using a modified stir casting method. the casting billets were deformed thoug...

the aim of the present study was to investigate the effect of quenching and tempering temperatures on themicrostructure, mechanical properties and the wear characteristics of medium carbon-high chromium wear resistantsteel. in addition, the dominant wear mechanisms were studied. for this purpose, austenitizing and temperingtemperatures were selected in the ranges of 900- 1000 °c and 300- 500 °c...

The aim of the present study was to investigate the effect of quenching and tempering temperatures on the microstructure, mechanical properties and the wear characteristics of medium carbon-high chromium wear resistant steel. In addition, the dominant wear mechanisms were studied. For this purpose, austenitizing and tempering temperatures were selected in the ranges of 900- 1000 °C and 300- 500...