The effect of the chemical distribution on the mechanical properties of the Al-5.5wt%Si-5wt%Zn-0.2wt%Mg alloy after thixoforging and solution heat treatment

The effect of heat and strain during the semisolid processing route on microstructural evolution mechanical performance Al-5.5wt%Si-5wt%Zn-0.2wt%Mg alloy was evaluated. as cast heated partially melted to 588 °C (fs = 0.40), thixoformed (in an open die forged) solution heat-treated (SHT) at 525 for 1 6 h. chemical distribution (SEM-EDS) main alloying elements were evaluated each step route. SHT 2.5 h after thixoforming showed be adequate considering (a) spheroidization Si crystals, (b) formation Fe- Mn-rich platelet-like particles in eutectic phase, (c) Mg dissolution from Mg2Si conglomerates (d) homogeneous Zn diffusion along entire part. As a consequence higher circularity secondary particles, possibility crack propagation under stress minimized. possible solute clusters GP zones containing Zn, Mg, Cu enabled due SHT, which increased alloy’s strength. Larger crystals spatial spread resulted hardness increase alloy.