Effects of doped elements on the cellular precipitation in Cu-10Ni-8Sn alloy

Abstract

The effects of additions of Ti, Si, Cr, Al, Co, Fe, In and Mn on the cellular precipitation in a Cu-10 mass%Ni-8 mass%Sn alloy were investigated by the quantitative mettallographic method. The additions of these elements suppressed the nucleation and growth of the grain boundary cell. The addition of Ti, Si, Al and Cr especially suppressed the growth of the cell. Excepting Al and Mn, the elements which showed the larger suppressing effect on the grain growth at solution-treatment temperature also showed the larger suppressing effect on the cell growth at aging temperature. In all of the as-quenched specimens containing additional elements excepting Mn, fine insoluble compound particles such as Ni3Ti and Ni31Si12 phases were observed. Therefore, it is considered that these fine insoluble particles suppressed the grain boundary migration at the solution-treatment temperature and also suppressed the migration of the advancing boundary of the cell at the aging temperature.