The advent of hot log shears and hot log saws helped the soft aluminum extrusion industry to transition from pre-cut billets to logs cut to length. This has helped the aluminum extrusion industry to increase its overall efficiency. On the other hand, there is an adverse and undesired consequence in the use of this technology. This undesired consequence is the use of a two-piece billet to improve recovery. The log shear and log saws generate a two-piece billet when the remaining log can no longer allow a full billet cut. In many cases, the use of a two-piece billet does not come without compromises. A two-piece billet is associated with the presence of a second transverse weld and a high occurrence of blisters in many shapes. The use of two-piece billets can reach, under certain circumstances, as high as 40 percent of the total billets run and therefore, it is essential for the extruder to better understand the extrusion process. This study is devoted to better understand the occurrence of blisters, the billet upset, and metal flow in a two-piece billet.
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