Improving the Physical Properties of Copper through Nano Additives Using Powder Metallurgy
Suha M. Ghareeb *
Physics Department, College of Education for Pure Science, Kirkuk University, Kirkuk, Iraq.
*Author to whom correspondence should be addressed.
Abstract
Many copper alloys suffer from weaknesses in certain mechanical properties, hindering their suitability for various industrial applications. Copper powder with 4% iron nanoparticles added as a constant-ratio reinforcement material was used, along with nano-alumina at varying reinforcement percentages (0, 2, 4, 6, and 8 wt%). A 10 mm diameter die was prepared to compress the mixed powders at a pressure of 5 tons for 3 minutes. The resulting samples were the same diameter as the die and 7 mm thick. These samples were sintered in a furnace at 900°C for 2 hours. Scanning electron microscopy (SEM) tests were performed on the samples after subsequent machining. The results showed that the addition of alumina improved the surface structure of the presses, achieving the best topographic surface at a 6% alumina content. Hardness testing was also conducted, yielding the highest microhardness of 126 kg/mm² at the 6% alumina content, which subsequently decreased. The compressive strength results showed that the optimal 6% alumina content yielded the highest compressive strength (220 MPa), which then decreased. The abrasive wear rate for the optimal content was (4.80 × 10⁻⁵ g/cm), which then increased. Thermal conductivity values decreased gradually with each addition of alumina, reaching its lowest point at the highest content of 8% (135 W/m.k).
Keywords: Alumina, copper, iron, mechanical, properties