Nanocrystallization of Al80Ni6Y8Co4Cu2 amorphous alloy
(1. State Key Laboratory for Advanced Metals and Materials,
University of Science and Technology Beijing;
2. School of Materials Science and Technology,
University of Science and Technology Beijing,Beijing 100083, P.R.China)
University of Science and Technology Beijing;
2. School of Materials Science and Technology,
University of Science and Technology Beijing,Beijing 100083, P.R.China)
Abstract: Nanoscale α(Al) phase with a size of 15 nm was precipitated from Al80Ni6Y8Co4Cu2 amorphous ribbons after annealing. The microhardness increases with increasing the crystallization volume fraction of nanoscale α(Al)phase. The combination effect of alloy strengthening and dispersion strengthening is main reason for the increase of microhardness. The formation of intermetallic compound (Al3Ni) with a small volume fraction leads to the decrease of microhardness resulting from the depletion of the solute elements in the residual amorphous matrix and the weakening of alloy strengthening. With increasing the volume fraction of intermetallic compound, microhardness increases again due to dispersion strengthening of nanoscale intermetallic compound.
Key words: nanoscale α(Al) particle; alloy strengthening; dispersion strengthening; microhardness