Research and Measurements of Velocity Field during Extrusion Process
نویسندگان
چکیده
Extrusion is one of the widest used and the most basic processes of plastic forming, and the metal flow in extrusion is affected by many factors, such as friction, die shape, billet temperature and so on. Among these factors, friction is the key boundary condition to determine the property of the extruded products. In this paper research and measurements of velocity fields and impact of friction on velocity distribution in forward extruded specimens of copper alloy were analysed using the visioplasticity method. The visioplasticity method was used to find the complete velocity distributions from the experimental data by the finite-difference method. Comparison was made between velocity distributions in the specimens extruded with different lubricants with different coefficients of friction. The results in a form of diagrams have shown that the influence of the lubricant’s coefficient of friction on the velocity distributions in extruded material can be of great importance especially in some critical regions in the cold formed material.
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