Simple compression test and simulation of an Sn–15% Pb alloy in the semi-solid state

A rheological investigation has been conducted using a simple compression test and a numerical simulation on a semi-solid Sn–15% Pb alloy with a solid volume fraction of 0.55 and 0.60. The stress–strain curve for the semi-solid state was divided into three zones; the first is the compaction zone, the second is the structure breakdown zone and the last is the thixotropic zone. Three sets of power law factors, one for each zone, were calculated. The factor m was larger than 1.0 in the first compaction zone, between zero and 1.0 in the second zone and less than zero in the third zone. The calculated load–stroke curves with the factors were compared with experimental results. The friction mechanism of the semi-solid forming process is different from that of conventional solid forming processes and therefore is discussed in more detail. The calculated curve with three sets of factors represents the experimental results comparatively well.