Effect of the Cu and Ni content on the crystallization temperature and crystallization mechanism of La–Al–Cu(Ni) metallic glasses

Abstract

The effect of the Cu and Ni content on the crystallization mechanism and the crystallization temperatures of La–Al–Cu(Ni) metallic glasses (MGs) was studied by differential scanning calorimetry (DSC). The experimental results have shown that the DSC curves obtained for the La–Al–Cu and La–Al–Ni MGs exhibit two and three crystallization temperatures, respectively. The crystallization temperatures of the La–Al–Cu and La–Al–Ni MGs result from the merging and splitting of thermal events related to the corresponding eutectic atomic pairs in the La72Cu28 and La81.6Al18.4 MGs, and La72Ni28 and La81.6Al18.4 MGs, respectively. In addition, Al- and Ni-containing clusters with weak or strong atomic interaction in the Al–Ni atomic pairs strongly affect the crystallization mechanism and thus the crystallization temperature of La–Al–Ni MGs. This study provides a novel understanding of the relation between the crystallization temperature and the underlying crystallization mechanisms in La–Al–Cu(Ni) MGs.

Effect of Fe Addition on Microstructure and Mechanical Properties of As-cast Ti49Ni51 Alloy

“…In addition, the Fe content in the matrix is larger than that in the second phase, which is related to the heat of mixing of Ti–Fe and Ni–Fe atomic pairs. The heat of mixing between atomic pairs can indirectly react with the interaction force between atoms pairs [31,32,33,34]. When the heat of mixing of atomic pairs is negative, the interaction force between atomic pairs is large, when the heat of mixing of atomic pairs is small negative or positive, the interaction force between atomic pairs is weak [31,34].…”

“…The heat of mixing between atomic pairs can indirectly react with the interaction force between atoms pairs [31,32,33,34]. When the heat of mixing of atomic pairs is negative, the interaction force between atomic pairs is large, when the heat of mixing of atomic pairs is small negative or positive, the interaction force between atomic pairs is weak [31,34]. The heat of mixing of Ti–Fe atom pair is −17 kJ⋅mol −1 [33], which is larger than that of Ni–Fe atom pair (−2 kJ⋅mol −1 [33]), indicating that the interaction force of Ti–Fe atom pair is larger than that of Ni–Fe atom pair.…”