Amorphization of M-Si (M=Ni, Co, Mo, Mn, and Cr) powders by ball milling using revolution-step-like-decreasing mode

Abstract

Amorphous alloy powders of the silicide type M-Si (M=Ni, Co, Mo, Mn, and Cr) are produced from crystalline elemental powders by high-energy ball milling using revolution-step-like-decreasing (RSD) mode. In the ball milling using the RSD mode, after promoting true chemical alloying in milled powder samples under high-vial rotation of the ball mill in the earlier stage, the medium- or low-vial rotations in the successive milling stages lead to amorphization of powder products due to making recovery processes, like nucleation of more stable phases, less prevailing. Amorphicity of the RSD milled powder samples is examined by x-ray diffraction and/or differential scanning calorimetry.