Fabrication of Metallic Glass-Based Nanocomposite by In-Situ IntermetallicNanocrystallization

In this study, nanocrystallization of metallic glass was used to fabricate an amorphous/intermetallicnanocomposite. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), anddifferential scanning calorimetry (DSC) were used to explore the phase analysis and thermal characteristicsof the metallic glass, while nanoindentation testing was used to determine the hardness and elastic modulus.DSC analysis showed that crystallization happened in a single step during heating and the onset temperatureof the crystallization peak is approximately ۶۶۰°C and the peak temperature is ۶۸۰°C. Furthermore, the resultsof this research showed that the formation of nano-sized intermetallics in the amorphous matrix significantlyincreased the mechanical properties of samples. Hard nano-size intermetallics of Ni۳Nb, Ni۶Nb۷, and Nb۳Ni۲Siwith an approximately average size of ۱۰ nm were formed after partial crystallization of metallic glass andreinforced the amorphous matrix significantly. The metallic-glass matrix composite reinforced with nano-sizedintermetallics was formed by partially crystallizing (Ni۶۰Nb۴۰)۹۵Si۵ metallic glass during non-isothermalheating. The results of the present research showed that the formation of hard nano-sized intermetallicsincreased the hardness and Young’s modulus from ۹.۹ to ۱۶ and ۱۳۱.۱ to ۲۰۷ GPa, respectively.

Keywords:

Nanocomposite , Intermetallic , Metallic glass , Nanocrystallization , Mechanical properties