Influence of thermal treatment on structure and microhardness of Fe75Ni2Si8B13C2 amorphous alloy

► Amorphous alloy undergoes a series of thermally induced structural transformations. ► Maximum hardness with nanocomposite of nanocrystals dispersed in amorphous matrix. ► Hardness decreases when crystallite size increases above 50 nm. ► Treatment at high temperature produces porous granulated structure (lower hardness). ► Changes in composition and crystal structure had no effect on microhardness.