Microstructural and Physical Characteristics of Recycling Aluminium Chips AA6061/Al Powder Using Powder Metallurgy

Abstract

Abstract-Solid state recycling of AA6061 chips by cold compression is a current approach processing technique that uses remarkably lower energies and operating cost compared to conventional recycling by casting. In this study, recycled AA6061 chips together with Al powder were fabricated to form a sample by combination of powder metallurgy and compaction technique. The effects of various Al powder content on the microstructure of the recycling AA6061/Al sample were investigated. The density, apparent porosity, water absorption and hardness of the composites were also examined. It was observed that the Al powders in the AA6061/Al composites were distributed non-homogeneously and randomly between the AA6061 chip regions. The density decreased gradually with the addition of Al powder rise back at 70 wt% content of Al powder until it reaches full Al powder. The density of sample full chips and full powder shows the closest value to theoretical at 2.47 g/cm 3 and 2.43 g/cm 3 respectively. The full Al chips showed the highest hardness at 65.6 Hv and gradually decreased with the increasing of Al powder content.

Microstructures and Tensile Characteristics on Direct Recycled Aluminium Chips AA6061/Al Powder by Hot Pressing Method

“…This was explained by Kadir et al, the increasing pore size was correlated directly with an increase in the irregularity of pore shape. Thus, the apparent porosity also related by chip and powder sizes contact in resulting the pores formation of the specimen body [11]. The microscopic analysis of the fracture surface in Fig.…”

The Effect of Microstructures and Hardness Characteristics of Recycling Aluminium Chip AA6061/Al Powder On Various Sintering Temperatures

“…Grain boundaries delayed dislocation movement and a number of dislocations within a grain have an impact on, thus causing the high hardness result on the surface of sample. Indirectly, the simply dislocations will traverse grain boundaries and travel from grain to grain [11]. However, to make sure that the data of hardness of the sample can be obtained accurately, the indention point on the sample must be pointed to the particle of the sample.…”

Effect of Heat Treatment on Tensile Strength of Direct Recycled Aluminium Alloy (AA6061)

“…From this reason nowadays, an economical process has been discovered instead of conventional recycling, and this process involves the direct treatment of the chip of the metal [2]. The method of treating and collecting metal machining waste is called metal chip processing, which uses metal crushers, oil separators, drying of the chip, and other specialized equipment [3]. A direct recycling of aluminum alloy machining chips into finished or semi-finished product is an alternative method to overcome the issue of losing material by using remelting of aluminum chips and to additionally build up the energy balance of the aluminum production [4]- [6].…”