With iron powder and aluminum powder as raw material, the rotating viscometer was used to measure the change of the viscosity of the slurry during the gelation process to investigate the gelation behavior to obtain high quality of the green body. The results show that: The increase of the initiator content, monomer content and reaction temperature will decrease both the idle time and the reaction time. The increase of catalyst content will significantly decrease the idle time while it has less impact on the reaction time. In turn, the reduction of the volume ratio of the monomer to the crosslinker reduces the reaction time, but has no influence on the idle time. Combined with the analysis of slurry stability, the idle time and reaction time can be control in range of 71~748 s and 154~714 s to realize the controllable gelation of products with different size and complexity by verifying the initiator content, the catalyst content, the reaction temperature, the monomer content and the volume ratio of the monomer to the crosslinker. the effects of these parameters on the idle time and reaction time has been systematically investigated. The controllable gelation can be realized by adjusting the idle time and the reaction time. Porous FeAl intermetallics with uniform pore structure, open porosity of 57.6 %, pore size below 10 μm, compressive strength of 40.7 MPa and complex shape fabricated by gel casting successfully match the demand of gas separation.