The hydrostatic extrusion is a new method of extrusion process. The most important advantage of this method is reduction of friction and close tolerance for the coating thickness. In this study, the hydrostatic extrusion simulation of bimetallic wires has performed using of finite element method. In the following the advantages of hydrostatic extrusion compared to the direct extrusion are prese...

Metal forming processes, compared with machining ones, reduce production steps and increase manufacturing speed in addition to saving raw material. In this paper, forming process of column of a steering mechanism is investigated by finite element analyses and experimental tests; and optimum die design parameters are found. Forming process parameters including die opening angle, bearing length, ...

Internal friction in concentrated alloys at kHz frequencies and at temperatures from 120 3 0 0 K has been studied in alpha-and beta-brasses as a function of grain size, temperature and pre-strain, and a statistical model has been proposed to account for the observations.

Using spheropolygon-based simulations and contact slope analysis, we investigate the effects of surface topography and atomic scale friction on the macroscopically observed friction between rigid blocks with fractal surface structures. From our mathematical derivation, the angle of macroscopic friction is the result of the sum of the angle of atomic friction and the slope angle between the cont...

Some results of the influence of y radiation on the mechanical properties of PoIymethylmethacrylate are presented. Doses of 0, 50, 100, 150 and 200 kGy were employed. The internal friction (loss tangent) and storage shear modulus were measured at temperatures between 173 K and 300 K using a damped torsion pendulum. Compressive tests were made at room temperature with strain rates between 1 . 4 ...

Nowadays the surface texturing has been widely recognized as a usable capability to improve the tribological systems. In this paper, ultrasonic assisted turning (UAT) isperformed to create the micro textures on the flat faces. Micro surface texturing ismade on the Al7075-T6 by the UAT in the face turning process. Then, the influences of cutting speed feed, vibration direction and vibration ampl...

foam injection is becoming a standard conditioning agent when tunnelling with an earth-pressure balanced shield, resulting in an increasing interest in this technique. the technique is mostly based on empirical rules and experience. to be able to determine what foam and how may foam has to be injected for different soils, it is necessary to know the mechanical parameters of the foam-water-soil ...