Master sintering curves (MSCs) were constructed for tape cast NiO, YSZ and NiO/YSZ composite materials using apparent activation energies obtained through dilatometry experiments. A rule of mixtures approach was demonstrated to be a useful analysis tool in understanding the activation energy of the NiO/YSZ composites since NiO and YSZ do not affect the sintering of the other phase. Prediction of the 48vol% NiO composite was less accurate because of competing sintering modes near the percolation threshold.