Cu-Ni-Sn系焼結体の時効特性

抄録

Cu-Ni-Sn system alloy had been found as high strength by causing the spinodal decomposition of the matrix. Properties of this alloy have been well investigated in the casting process, but not so well in the PM process. Therefore, the sintering and heat treating experiments using each of alloyed and mixed powders of Cu-9mass%Ni-8mass%Sn system carried out to reveal the better condition in the PM process. The results indicated that the sintered compacts using alloyed powder had all homogeneous structures, but those using mixed powder had heterogeneous structure. Furthermore, when sintered compacts using alloyed powder was aged at 623 K for 3.6 ks after sintering, it showed the highest strength with characteristic modulated structure caused by spinodal decomposition. In addition, it was necessary to cool the sintered compacts down to 573 K within 260 s after sintering to obtain supersaturated solid solution avoiding aging during the cooling process.