Thixoforming of laminate made from semisolid cast strips

In order to reduce the cost of the feedstock, a laminate, in the form of a slug, made from roll cast strips has been used as feedstock for thixoforming. The size of the laminate cube was 40 mm × 40 mm × 40 mm. A high-speed twin roll caster was used to cast A356 strip from which the laminate was manufactured. The strip thickness varied from 3 mm to 2 mm, when the strip was cast at the speed from 30 m/min to 90 m/min. The strip was cast from semisolid slurry that was produced using a cooling slope. The solid fraction of semisolid slurry was lower than 10%. The primary crystal of the strip become spheroidal when heated up to semisolid condition. The ability of the laminate to flow, in the semisolid condition, was similar to that of conventional feedstock for thixoforming. The mechanical properties of the thixoformed strip laminate were: tensile strength of 315, 253 MPa, 0.2% proof stress and 8% elongation.