Structural modeling of Pd–Si and Fe–Zr–B amorphous alloys based on the microphase separation model

“Microphase separation” structure models were constructed for amorphous Pd82Si18 and Fe90Zr7B3 alloys using the reverse Monte Carlo χ2 calculation. The input experimental data were atomic pair distributions obtained from these alloys by electron diffraction. The calculations were based on two initial structure models: (1) with local α-phase atomic clusters embedded in a dense-random-packing (DRP)-matrix and (2) with an entirely DRP structure. It was concluded that fcc-clusters as small as 1–2 nm in size with a volume fraction less than 20% and bcc-clusters less than 1 nm with a larger volume fraction (about 40%) are distributed in the DRP-like matrices in the Pd–Si and Fe–Zr–B alloys, respectively. The matrix structure in the Pd–Si alloy is mainly composed of the trigonal prisms surrounding Si atoms.