The microstructure of electrodeposited amorphous or microcrystalline Fe-P alloys

Abstract

Dependent on$\bar cFe_{1 - \bar c} P_{\bar c}$ is produced through electrodeposition in three modifications: microcrystalline if$0.01< \bar c< 0.115$, amorphous if$0.15< \bar c< 0.28$ and in a mixed state containing both components if$0.115< \bar c< 0.15$. The interpretation of results of large and small angle X-ray scattering, of measurements of the coercivity and of the mechanical density shows that the three modifications consist of two phases. The structure of the grain boundary phase in the microcrystalline alloys differs considerably from that of the amorphous phase. This arises from the dependence of the atomic volume on the average phosphorus content$\bar c$. The volume fraction of the crystalline component decreases with increasing$\bar c$ up to$\bar c \approx 0.15$. But even in alloys revealing X-ray patterns without any peaks coming from crystalline particles small angle X-ray scattering indicates the existence of metal-rich inclusions occupying some percent of the total volume.