Effect of Sintering Temperature on Aluminium Chip Recycling (Al7075) by Powder Metallurgy Process

Abstract:

Al7075 was recycled using the powder metallurgy technique to determine the effect of particle size distribution on the mechanical and microstructure of materials. Analysis of the microstructure, green density and microhardness was conducted to evaluate the performance of the recycled aluminium. The Al7075 was added with 4% of alumina and Al₂O₃ (3-4μm). The results showed that the green density of recycled Al7075 was lower than the pure Al7075. The average size distribution of the aluminium powder decreased with the increase in the ball mill time. As the temperature of sintering process increased, the green density decreased. The alloy’s microstructure sintered at 650°C has the lowest density, indicating a larger and more frequent porosity. The hardness of the samples with the addition of alumina was higher than the samples without the alumina. Sintering at 650°C also caused the hardness of the sample to increase in the range of approximately 50-62 Hv.

• Periodical: Applied Mechanics and Materials (Volume 761)
• Pages: 352-357
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.761.352
• Online since: May 2015
• Authors: Y.F. Fuziana*, Mohd Warikh Abdul Rashid, M.A. Lajis, Mohd Asyadi Azam, Ahmad Hariz Mustaffa
• Keywords: Al7075, Aluminium Alloy, Aluminium Chip, Aluminium Recycling, Direct Conversion Recycling, Metal Matrix Composite, Powder metallurgy

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