The structure of nanosecond-pulse laser-melted surfaces of different evaporated layers and bulk ingots has been studied using room-temperature conversion-electron Mössbauer spectroscopy in the iron-boron system between 17 and 56 at. % B content. Considerable decrease (10%) of the width of the iron hyperfine field distribution was observed for the laser-melted surfaces compared with the evaporated layers, indicating an enhanced disorder in the latter. Amorphous alloys were obtained in the 17 33 at. % B composition range by laser melting. No amorphous alloy was obtained by the laser melting of the equiatomic FeB ingot or the evaporated amorphous Fe44B56 film. In the latter case the laser melting has resulted in the low-temperature crystalline -FeB modification, indicating the important role of surface nucleation.
ASJC Scopus subject areas
- Condensed Matter Physics