The paper reports a new approach for controling the precipitation of copper and tin containing phases in steel in order to enable defect-free hot-formign of recycled steels. It also describes the suitability of the utilisation of aluminium (as scrap) for controlling the deleterious effects of copper and tin during the secondary steelmaking process. The approach adopted for the formation of stable intermetallic phases containing tin and copper is based on the comparison of the phase stability diagrams. The selection criterion of alloying elements for forming stable intermetallic phases is also described. The mechanism of intermetallic precipitate formation after mechanical deformation and heat treatment of steels to which excessive amounts of microalloying additions have been made is described. The results from alloy melting and heat treatment are presented, along with evidence for the suppression fo grain-boundary segregation of copper and tin-containing phases.
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