The investigation of Al7075 and Al7075+1wt.% Zr alloys prepared by spark plasma sintering technology
Abstract
The development of high strength materials with sufficient deformability requires new processing routes. Powders with fine grain structure and special phase composition can be prepared by powder metallurgy.
Spark plasma sintering (SPS) enables the conservation of such microstructure in the compact material. Compacts of aluminium alloys were prepared by SPS (500 oC for 3 min) of gas atomised powders.
The grain structure remained unchanged during SPS, but significant changes in the distribution of phases were observed by scanning electron microscopy. The microhardness of sintered samples was measured after thermal treatments.
The grain size remained unchanged during annealing at even 500 oC for 10 hours, but the materials' microhardness changed significantly as a result of changes in the phase composition. The materials exhibited both artificial and natural ageing.