|顆粒形狀對純銅粉末微逆向擠製之影響=Effect of Particle Shape on Micro Backward Extrusion of Copper Powder
Micro backward extrusion;
|本研究針對樹枝狀與球狀之純銅粉末，於室溫下利用微粉末壓縮與微逆向擠製技術，分別製作直徑為1 mm、2 mm及3 mm之圓柱與圓杯成品，並以600 ºC進行真空燒結，完成微型純銅元件之製作。本研究探討顆粒形狀對元件之硬度分布、孔隙率及顯微組織之影響。其中，圓柱粉末成品也用於簡單壓縮試驗，以瞭解應力應變曲線之特性。研究結果顯示，成形負荷的增加可降低孔隙率。此外，與樹枝狀粉末成品比較，球狀粉末成品有較低之孔隙率、較高之相對密度及較高之平均硬度。
|This study investigated the effect of the particle shape on the micro backward extrusion of copper powders. Spherical and dendritic particles of copper powders were used in compression and backward extrusion processes to form cylindrical billets and cups, respectively, with different diameters of 1 mm, 2 mm and 3mm. After the produced products were sintered at 600 ºC for 1 hour and cooled in the furnace, their porosities, hardness distributions and microstructures were examined. The cylindrical billets were also used in simple upsetting tests for obtaining the stress strain curves in order to understand their deformation behaviors under compressive stress. The results showed that the products from spherical particles had lower porosities and higher relative densities. The porosity increased with the forming load. Moreover, the products from spherical particles had greater hardness values than those from dendritic particles.