Non-isothermal crystallization kinetics and mechanical properties of Al 86Ni 6Y 4.5Co 2La 1.5 metallic glass powder

The crystallization kinetics and mechanical properties of Al86Ni6Y4.5Co2La1.5 metallic glass powder have been investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM) and nanoindentation. The first crystallization stage of the Al86Ni6Y4.5Co2La1.5 glass powder is identified to be a surface nucleation and one-dimensional growth process while the second and third crystallization stages are characterized by volume nucleation but followed by one-dimensional growth and two-dimensional growth, respectively. The hardness and elastic modulus show opposite trends on crystallization; they are both sensitive to the precipitation of fcc-Al, growth of fcc-Al and precipitation of complex intermetallic phases. The changes of hardness and elastic modulus of the Al86Ni6Y4.5Co2La1.5 metallic glass powder with crystallization are discussed.