Investigating the Morphology, Hardness, and Porosity of Spherical and Dendritic Copper Powder Filters Produced via Cold Isostatic Pressing

PorosityPorosity in copper filters is sensitive to powder type and space holder material in addition to fabrication processing conditions. This study is focused on the use of two different copper powderCopper powder types (spherical and dendritic) to produce air flow filtersAir flow filtration. The hydraulic pressing method was used to produce copper filters under varying pressure with different spacer (polyvinyl alcohol (PVA)) concentrations. Following compaction, the samples were thermally sintered in two segments at 200 °C and 750 °C. The morphologyMorphology, porosityPorosity, and mechanical propertiesMechanical properties of the sintered samples were characterized. The morphological analysis demonstrated better consolidation and overlapping of copper powderCopper powder particles in samples with a higher weight percentage of the spacer material (PVA). The highest porosityPorosity was achieved in the sample produced using dendritic copper powderCopper powder mixed with the highest weight percentage of PVA (3%). As a porous structurePorous structure, the (Vickers) hardness of the samples greatly varied within the samples. Samples prepared with spherical powders at comparatively high pressures demonstrated the highest hardness. The results achieved in this study demonstrated that copper filters with 14% to 26% porosityPorosity can be produced using spherical and dendritic copper powdersCopper powder by controlling the compaction pressure from 635 to 793 MPa.