Gelcasting of alumina ceramics (2) gelation of the suspension

The pilot study has been carried out for processing details of gelcasting alumina ceramics, including amount of monomer, ratio of monomer and linker MBAM, amount of initiator APS and solid content of alumina aqueous suspension. The tests showed that the green part with enough strength for machining could be prepared when the amount of monomer AM was 24% (mass percent) in premix, the ratio of the amount of AM to that of MBAM was below 24% (mass percent) and the amount of APS was above 0.014 ml. As high as possible content loading of solid phase to keep enough fluidity of the slurry is beneficial for both high green density and strength. Besides, vacuum deairing of the slurry can obviously improve the green strength.