Behavior of Pores in the Sintering of Acicular Fe2O3 Powder

The sintering of acicular Fe₂O₃ powder was studied by isothermal dilatometry, hysteresis Hg porosimetry, and SEM of powder compacts using a resin-impregnating technique, and compared with an ordinary equiaxed powder. It is shown that the pores in the acicular powder compacts remain connected until a later stage of sintering than those in the spherical powder, and that the observed rapid initial densification, along with preferential shrinkage in the parallel-to-pressing direction, can be interpreted in terms of particle rearrangement.