Exafs studies on the local structure of transition metal-based amorphous alloy: -Structural rearrangement of amorphous CU 60ZR 40 alloy during the crystallization process

Abstract

Short range structural changes of amorphous Cu60Zr40 alloy during the crystallization process have been investigated by EXAFS (Extended X-ray Absorption Fine Structure spectroscopy) at both the Cu and Zr K-absorption edges. The Cu K-edge EXAFS spectra were reconstructed well by using combinations of four subshells. A weak increase of the Cu K-edge EXAFS spectrum observed in the alloy heated at 623 K is due to the increase of the amount of neighboring atoms in the 3rd and 4th shells, which was caused by the reduction of structural disorder and the short range structural rearrangement accompanied by the structural relaxation. While, the increase of the Zr K-edge EXAFS spectrum in the alloy heated at 773 K suggests that the aggregation of zirconium atoms occurs and induces the formation of the multi-phases.