Evolution of micro structure and non-equilibrium phases in electron beam treated Zr_(55)Cu_(30)Al_(10)Ni_5 bulk amorphous alloy

摘要

Electron beam (EB) is becoming very popular for the modification of the surfaces as it involves localized melting and fast cooling which helps in achieving the non-equilibrium phases as well as fine microstructure. Surface modification of Zr-based amorphous alloy Zr_(55)Cu_(30)Al_(10)Ni_5 has been carried out by EB melting. Differential scanning calorimetry (DSC) was employed to determine the supercooled liquid region and activation energy of crystallization. The as-cast and modified surfaces of amorphous alloy at different beam conditions were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. Various phases like NiZr_2, CuZr_2 and Cu_(10)Zr_7 were identified which resulted in the enhancement of hardness of the modified alloy surface.