Comparison of Different Extrusion Methods for Compaction of Powders

Abstract:

Densification of metallic powders by means of extrusion is regarded as a very attractive processing technique that allows obtaining a high level of relative density of the compact. However, the uniformity of the relative density depends on that of strain distribution and on the processing parameters. Several variants of extrusion can be used for compaction of metal particulates, including the conventional extrusion (CE) and equal channel angular pressing (ECAP), often referred to as equal-channel angular extrusion. Each of these processes has certain advantages and drawbacks with respect to compaction. A comparative study of these two extrusion processes influencing the relative density of compacts has been conducted by numerical simulation using commercial finite element software DEFORM2D. The results have been validated by experiments with titanium and magnesium powders and chips.

• Periodical: Materials Science Forum (Volumes 667-669)
• Pages: 57-62
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.667-669.57
• Online since: December 2010
• Authors: Andrey Molotnikov, Rimma Lapovok, Tao Peng, Yuri Estrin
• Keywords: Equal-Channel Angular Pressing (ECAP), Extrusion, Finite Element Model (FEM), Powder Compaction

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