The Impact of Alloying Additives on the Shrinkage Processes and Corrosion Resistance of Lead-Free Casting Brasses

The article presents a comparative analysis of lead-free brass (CB771) and lead-containing brass (CB770). The study aimed to assess shrinkage processes and corrosion resistance. CB771 samples with modified chemical composition, enriched with zinc, aluminum and tin, were compared with CB770 samples in terms of casting shrinkage and susceptibility to dezincification. Dilatometric analysis revealed that different alloying additives affect shrinkage and dimensional stability at high temperatures in various ways. Aluminum and tin significantly improved resistance to dezincification, while the addition of zinc proved to be less effective. Microscopic examinations confirmed that alloys with aluminium and tin additives have a finer structure, which can translate to higher mechanical properties. The results suggest that lead-free alloys can replace traditional alloys in sanitary applications, reducing the negative impact of lead on the environment and public health.