AN EFFORT ON PREPARING SINTERED BODIES OF FE4N

Sintered bodies of Fe4N were prepared by way of a hot-press, followed by firing in an atmosphere containing NH3 and H-2 gases. After the hot-press, Fe4N was not sintered and impurities of an iron oxide and a paramagnetic compound coexisted. The sintered bodies were obtained by firing the hot-pressed bodies in the atmosphere. It was found that, in firing, Fe4N was reduced and sintered above the decomposition temperature (approx. 670-degrees-C) and then the sintered bodies were rapidly renitrified in the atmosphere to Fe4N through open pores in cooling. X-ray diffraction and Mossbauer spectra showed that the sintered bodies were Fe4N single phase.