The present paper is focused on the microstructure of the Ni-P thin layers crystallized from the amorphous state. The layers in this study have been produced by a chemical reduction method. They have been crystallised in order to obtain mixed amorphous-crystalline and polycrystalline microstructures. During the very early stages of crystallization there is possibility to produce nanocrystalline materials.
Three microstructures obtained by annealing at the temperatures 270 and 320oC, i.e. below the peak of crystallization (370oC) are described. Earlier results of the same authors showed that nanocrystals appear in Ni-P layers. The X-ray study, calorimetric analysis and microstructure observations carried out on transmission electron microscope in this study revealed the transition from amorphous to crystalline microstructure and changes in the morphology of grains. Crystals with different sizes have been observed, some of them in the nano-metres range.
Some kind of correlation has been found between the P concentration in amorphous Ni-P material and the microstructure at the front of crystallization. The crystallization starts in the area exhibiting lower concentration of the phosphorous. The appeared crystals in this region have an elongated shape and form bands separated by amorphous material.