Iron oxide scaffolds with gradient porosity were fabricated using the freeze-casting technique. Doped iron oxide particles were employed to generate stable particle suspensions in camphene using the ball-milling technique. Viscosity measurements were performed to determine the effect of the milling time and the additive incorporation. The freeze-casting process implemented in this work created a wide diversity of solidification front velocities, (2–80 µm s−1), and thermal gradients, (0.2–20°C cm−1) during sample fabrication. The solidification problem of liquid/solid systems has often been reviewed, but usually only under steady-state conditions. This study presents a much simpler approach for the correlation of the average dendrite arm spacing and pore morphology with different processing parameters.
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(2–80 µm s−1), and thermal gradients,
(0.2–20°C cm−1) during sample fabrication. The solidification problem of liquid/solid systems has often been reviewed, but usually only under steady-state conditions. This study presents a much simpler approach for the correlation of the average dendrite arm spacing 
and pore morphology with different processing parameters.