Recovering and Hot Deformation Processing of Recycled Spray Formed 7055 Aluminum Alloy Powders

Around 20% of powders are scattered as waste outside the deposition chamber during spray forming of AA7055. To recycle these valuable powders, a recovery and a hot deformation processing routes are developed. Firstly, strict screening of powder is established in which the chemical compositions and microstructure are measured. Cold isostatic pressing followed by hot extrusion and T76 or T6 heat treatment is developed to compact the powders into a solid bar shape which could be used as billets. The hyperbolic sinusoidal constitutive equation is obtained using Gleeble hot compression test of the densified material. The analysis of mechanical properties shows the samples after T76 heat treatment possess slightly lower strength but enhanced toughness than that of sprayed samples. Thus, further deformation processing like forging is needed to improve compactness and mechanical properties of these billets.