Pengaruh Penambahan Elemen (Al/CNT) terhadap Sifat Mekanis dan Struktur Mikro Paduan (Fe/Cu) dengan Metode Metalurgi Serbuk

Abstract

Powder metallurgy is a manufacturing method that allows the production of materials with superior mechanical properties and homogeneous microstructure through the process of mixing, pressing, and sintering metal powders. This study examines the effect of the addition of Aluminum (Al) and Carbon Nanotube (CNT) elements on the mechanical properties and microstructure of Fe/Cu alloys. Al-CNT addition variations used are 0.5 wt.%, 1 wt.%, and 1.5 wt.% with premilling process using high energy ball mill, and 1.5 wt.% Al-CNT without premilling process. The test results showed that the highest density was obtained in the alloy with 0.5 wt.% Al-CNT composition at 6.06 g/cm³, while the lowest density was found in the 1.5 wt.% Al-CNT composition without premilling with a value of 5.61 g/cm³. The highest Vickers hardness of 87.7 VHN was achieved in the 1.5 wt.% Al-CNT composition with premilling, while the lowest hardness of 76.3 VHN was found in the 0.5 wt.% Al-CNT composition. Compressive testing obtained the highest yield stress value of 278.414 MPa in the 1.5 wt.% Al-CNT composition with premilling, and the lowest value of 215.333 MPa in the 0.5 wt.% Al-CNT composition. The highest wear rate was found at 0.5 wt.% Al-CNT composition of 4.98 × 10-⁷ mm³/Nmm, while the lowest wear rate of 2.59 × 10-⁷ mm³/Nmm was achieved at 1.5 wt.% Al-CNT composition with premilling. The addition of Al-CNT consistently improved the alloy microstructure by reducing porosity from 2068 porosity at 0.5 wt.% to 1218 porosity at 1.5 wt.% Al-CNT with premilling. The premilling process proved capable of further reducing porosity, where at 1.5 wt.% composition without premilling, the number of porosities reached 1820. These results indicate that the addition of Al-CNTs and the premilling process have a significant effect on improving mechanical properties, reducing porosity, and improving microstructure distribution in Fe/Cu alloys.