Solid state recycling of aluminum machined chip wastes by compressive torsion processing

The compressive torsion process (CTP) is applied for consolidation of aluminum machined chip wastes to investigate a possibility of a new solid state recycling for aluminum alloy. The machined chips were consolidated by the CTP under the different temperatures and rotation times, and then the microstructure and tensile properties were investigated. It was possible to consolidate aluminum chips sufficiently into a cylindrical specimen by the CTP even at room temperature. The tensile strength of the specimen processed by the CTP was higher than that of annealed alloy made from an ingot metallurgy process. The tensile strength increased as the processing temperature decreased. The enough elongation over 15% was also obtained all over the specimen processed at room and elevated temperatures. It was concluded that the CTP had the availability of a new solid state recycling process with upgrading of aluminum alloy.