The crystallization kinetics of amorphous Mg-Ni-Y alloys of different compositions, in which the concentration of yttrium was varied from 0 to 4%, were studied by differential scanning calorimetry (DSC) and X-ray diffraction and the mechanical spectroscopy techniques. It was shown that the transition from the amorphous to the crystalline state in the Mg-Ni-Y alloys went through several stages with precipitation of a metastable MgxNiy phase. The appearance of this phase was accompanied by a sharp increase in the Young's modulus and a large internal friction (IF) peak. The temperature of IF peak was shifted to higher values as the yttrium content increased. This shift is explained by the change in the activation energy of the structural rearrangement, as was confirmed by DSC and the Young's modulus studies. The MgxNiy phase is stable at ambient temperatures and its Young's modulus and microhardness are higher than those of the stable crystalline phases in the Mg-Ni-Y alloy structure.
|Number of pages||8|
|Journal||Physica Status Solidi (A) Applied Research|
|State||Published - 1 Jun 2001|