. It is believed that FeP experienced sintering and
agglomeration increasing the particle size to lengthscales that are
now in excess of the diffusional lengthscale. During the oxidation,
a similar reduction in weight gain was observed for the iron oxide
powders due to sintering or agglomeration. Values for the 80–
160 lm and 40–80 lm particles were similar in both cycles,
although the larger particles presented a higher oxidation rate