Effect of Grain Size on Cross Wedge Rolling of Micro Copper Rod

Abstract:

This study investigated the effect of grain size on the cross wedge rolling of micro copper rod. Annealing techniques and equal channel angular extrusion were employed to refine the grains of copper, after which the treated copper was machined to prepare the cylindrical billets with 1 mm diameter for conducting experiments. The billets were rolled between a pair of the dies fixed in a developed cross wedge rolling system to form micro copper rods. The results show that the developed system was able to successfully produced micro copper rods. The grain refinement led to a higher hardness and thus a greater forming load. The rod with fine grans had a larger concave curvature radius of the end face. The grain size clearly influences the material flow in the cross wedge rolling processes of the micro copper rod.

• Periodical: Key Engineering Materials (Volumes 622-623)
• Pages: 905-911
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.622-623.905
• Online since: September 2014
• Authors: Chao Cheng Chang*, Yao Sheng Hsiao
• Keywords: Cross Wedge Rolling, Grain Size, Micro Metal Forming

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