The Formation of Amorphous Structure During Irradiation of Fe--30% Ni Alloy by Phosphorus Ions

The relation between structure changes and element composition of Fe--30% Ni alloy during irradiation by P exp + ions with an energy of 80 keV was investigated by transmission electron microscopy and Rutherford backscattering spectrometry. Irradiation doses were from 10 exp 16 to 4 x 10 exp 17 ions/cm exp 2 . Within the dose range of 4 x 10 exp 16 to 8 x 10 exp 16 ions/cm exp 2 , phosphides of (Fe,Ni) sub 3 P type, having a tetragonal structure, were formed. At a dose of 1.7 x 10 exp 17 ions/cm exp 2 the amorphization of Fe--Ni film was observed. At higher implantation doses crystal material was obtained, containing phosphide phases with high P content. The composition of the amorphized films corresponds to a deep eutectic in the system metal--P. As it is known the alloys of Fe, Ni with boron or P of composition near to eutectic may be easily obtained in the amorphous state by a rapid quenching from fusion or by other methods. In the case the layer of Me--P eutectic is formed during P implantation and then the radiation amorphization of the implanted layer takes place.