Effect of chip treatment on chip-based billet densification in solid-state recycling of new aluminium scrap
Document Type
Conference Item
Publication Date
1-1-2020
Abstract
In solid state recycling of new aluminium scrap, processes prior to hot extrusion play an important role in order to obtain free-defect microvoid extrudates. The microvoid is formed due to air entrapment that came from porous chip-based billet. In this work, chip-based billet made from annealed and non-annealed chip was investigated to determine the effect of annealing on density, void pattern and hardness. AA6061-T651 chips were prepared as annealed and non-annealed and then compacted in die. The billets density and appearance were measured and visually inspected. Density measurement found that billet made from annealed chip has the highest relative density of 96.9%. Visual inspection and microstructure examination disclose that voids are present in the billet for both types of chip in which nonannealed chip is more obvious. The voids has distributed in homogeneously along the axial and vertical due to pressure gradient. The pressure gradient also affects the hardness distribution. The effect of strain hardening is more obvious at the peripheral compared to the centre. The average hardness of annealed chip is 49.5 HV0.1 while non-annealed chip recorded 89.5 HV0.1. In general, annealing treatment before compaction had softened the chip, reduced the hardness and strength, permitted large plastic deformation and improved billet density.
Keywords
Solid state recycling, Chip treatment, Densification, Cold compact, Chip-based billet
Divisions
mechanical
Funders
Ministry of Education, Malaysia (H085)
Publisher
SPRINGER-VERLAG SINGAPORE PTE LTD
Publisher Location
152 BEACH ROAD, #21-01/04 GATEWAY EAST, SINGAPORE, 189721, SINGAPORE
Event Title
4th International Conference on Mechanical, Manufacturing and Plant Engineering (ICMMPE)
Event Location
Melaka, Malaysia
Event Dates
14-15 November 2018
Event Type
conference
Additional Information
4th International Conference on Mechanical, Manufacturing and Plant Engineering (ICMMPE), Melaka, Malaysia, Nov 14-15, 2018