A bar-shape hot tearing test and measurements of freezing contraction were carried out on brasses containing elements such as Pb, Si, Sn, Al, Ni and Mn to give variety to the dendritic structure. The
α-phase in the binary Cu-Zn alloys grows more dendritically than the
β-phase. The
β-phase grows in nearly a cellular form. The
α-phase binary Cu-Zn alloys have less fraction solid at contraction start and poorer resistance to hot tearing than the
β-phase alloys. The proportion of the secondary dendrite arm length to the spacing increases and the tear-resistance is weakened both in
α-brasses containing Si and Sn and in the
β-brasses containing Pb, Si, Sn and Al. The fraction solid at start of contraction decreases with increasing the proportion of the secondary arm length to the spacing.
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