Pengaruh Variasi Tekanan Kompaksi Terhadap Karakteristik (Cunimn)-Xal Medium Entropy Alloy Menggunakan Teknik Metalurgi Serbuk

Abstract

This study investigates the effect of compaction pressure variation on the characteristics of (CuNiMn)-xAl medium entropy alloy (MEA) synthesized using the powder metallurgy technique. The research aims to evaluate how mechanical and physical properties of the alloy are influenced by changes in compaction pressure and aluminum content. The alloy consists of equiatomic copper, nickel, and manganese, with additional aluminum at 0.5 wt.% and 1.5 wt.%. The compaction process was carried out using warm compaction at 150 °C for 15 minutes with applied pressures of 250 MPa and 290 MPa, followed by sintering at 900 °C for 1 hour. The specimens were tested for density, hardness (Vickers test), wear resistance (using a pin-on-disc tribometer), microstructure (via optical microscopy), and surface morphology using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results indicated that the combination of 290 MPa compaction pressure and 1.5 wt.% aluminum addition yielded the best properties, with a maximum density of 4.59 g/cm³ and hardness of 430 HV. Aluminum addition enhanced microstructural densification and reduced porosity, while higher compaction pressure increased particle bonding. SEM-EDS analysis revealed a homogeneous elemental distribution and the formation of dominant Cu-Ni-Mn-based phases, along with oxygen presence due to aluminum's high affinity for oxidation during sintering. Overall, the combination of optimized compaction pressure and aluminum content significantly improved the alloy's mechanical performance. The developed (CuNiMn)-xAl alloy shows promising potential as an alternative material for mechanical components, particularly bushings, due to its high hardness, optimal density, and excellent wear resistance.