Crystallization of amorphous Al_(84.2)Ni_(10)La_(2.1)Ce_(2.8)Pr_(0.3)Nd_(0.6) alloy

摘要

The crystallization of amorphous Al_(84.2)Ni_(10)La_(2.1)Ce_(2.8)Pr_(0.3)Nd_(0.6) alloy was investigated by using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM) techniques. The amorphous Al_(84.2)Ni_(10)La_(2.1)Ce_(2.8)Pr_(0.3)Nd_(0.6) alloy crystallizes through the primary precipitation of fcc-Al phase from the amorphous matrix in the range of 490-550K, followed by the precipitation of Al_3Ni and Al_(11)(La, Ce)_3 phases in the temperature range of 590-680 K. Comparing amorphous Al_(84.2)Ni_(10)La_(2.1)Ce_(2.8)Pr_(0.3)Nd_(0.6) and Al_(84)Ni_(10)Ce_6 alloys, the addition of La can improve the precipitation of primary fcc-Al phase upon reheating the samples. On the basis of the Kissenger equation, the activation energy for crystallization of Al_3Ni phase is higher than that of the other two phases, fcc-Al and Al_(11)(La, Ce)_3 phases, implying that the thermal stability of the Al_3Ni phase is higher than that of the other two phases.