Taguchi optimization of electrolytic Cu powders recycled from scrap Cu plates and properties of recycled Cu compacts processed by hot-pressing

This study investigates the sustainable production of high-purity copper powders obtained from recycled scrap copper sheets through the electrolysis method. With increasing environmental concerns and the growing need for resource efficiency, recycling-based copper powder production has emerged as an attractive and sustainable alternative to conventional production methods. The study aims to optimize electrolysis parameters affecting powder morphology and properties in order to enhance the industrial applicability of the material. The Taguchi method was applied to optimize current density, solution concentration, and electrode distance, focusing on their effects on average particle size and apparent density. An orthogonal array design and ANOVA analyses were employed to identify optimal processing conditions. Material characterization was performed using scanning electron microscopy (SEM), laser particle size analysis, X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The synthesized dendritic copper powders were grouped by average size (21.61 μm, 52.24 μm, and 87.97 μm) and subsequently densified by hot-pressing to evaluate their physical, mechanical, electrical, and thermal properties. Samples with an average size of 52.24 μm exhibited the best overall performance, achieving 98.5% IACS electrical conductivity, 317 W/m·K thermal conductivity, 124 HB hardness, and 137 MPa tensile strength. The results demonstrate that recycled electrolytic copper powders can achieve high performance levels while simultaneously supporting sustainable production practices and improved industrial efficiency.