Design of the optimum preform for near net shape manufacturing is a crucial step in upsetting process design. In this study, the same is arrived at using artificial neural networks (ANN) considering different unequal interfacial friction conditions between top and bottom die and billet interface. Back propagation neural networks are trained based on finite element analysis results considering f...

The development of robust infrared fibers is crucial for harnessing the capabilities of new mid-infrared lasers. We present a novel approach to the fabrication of chalcogenide glass fiber preforms: one-step multimaterial extrusion. The preform consists of a glass core and cladding surrounded by a built-in, thermally compatible, polymer jacket for mechanical support. Using this approach we extru...

The paper reports an investigation into the forging of solid powder circular disc with large slenderness ratio, between two flat dies. The deformation pattern during the operation is influenced by many factors, which interact with each other in a complex manner. The decisive factors are the interfacial conditions, initial relative density of the preform and the geometry of the preform. An attem...

The manufacture of optical fibers typically involves taking a solid glass cylinder (a blank or preform), heating it up to melting temperature by feeding it through a cylindrical furnace (the drawing tower), and drawing the molten blank from the other end of the furnace at high speed (tens of meters per second). Since the drawing speed is much faster than the feeding speed (by a factor of at lea...

In this essay, a combination of neural network and genetic algorithm has been studied for optimization of the preform in close die forging. Finite Volume Method (FVM) is used as a simulation tool for forging processes. The simulation results have used in the neural network and the genetic algorithm has been employed to optimize the forging force. The neural network was used in three stages for ...

Abstract Preform is one of the important factors affecting mechanical properties textile composites. To further reflect influence preform structure on composite materials, angle interlocking and plain weave structures are configured in a certain proportion to form fabric with both structures. The results show that compound has positive effect improvement AERC. An increase organization configura...

RIFT (Resin Infusion under Flexible Tool) process modelling requires accurate material data like resin viscosity, reinforcement compressibility and reinforcement permeability. During the mould closing, the compression phase and the resin flow are important stages that strongly influence the quality of the obtained parts. In RIFT process the upper mould is a formable vacuum bag: its flexibility ...

We have studied the generation mechanisms of two different radiation-induced point defects, the Ge(1) and Ge(2) centers, in a germanosilicate fiber and in its original preform. The samples have been investigated before and after X-ray irradiation using the confocal microscopy luminescence and the electron paramagnetic resonance techniques. Our experimental results show the higher radiation sens...

In order to obtain the high-performance composites with high density, the influence of additional ultrasonic vibration on the infiltration of molten aluminum alloy (ASTM A336.0) into nickel porous preform by low-pressure and pressureless casting was investigated. There was no effect of ultrasonic vibration on infiltration distance under pressureless casting because of presence of surface oxide ...