中国科学院材料磨损与防护重点实验室/先进润滑与防护材料研究发展中心知识库

A novel method with the combined technology of soft lithography and centrifugal casting was developed to fabricate ceramic microparts. A well-dispersed aqueous alumina suspension suitable for micromolding was prepared. The suspension was filled into microstructured polydimethylsiloxane molds followed by consolidation under centrifugal force. Compared with the micromolding under gravity, denser particle packing was achieved for the green microparts under centrifugal force. The centrifugal force enhanced sedimentation of the alumina particles at a short time and thus the green density was significantly improved. A flexible polyethylene film was used as the substrate to prevent crack formation during drying, which allowed unconstraint shrinkage and reduced the buildup of strain energy. After sintering, the linear shrinkages of the microparts under centrifugal force were lower than those under gravity. The microparts under centrifugal force were fully densified and had good shape retention. The novel method, called centrifuge-assisted micromolding, has been demonstrated by the fabrication of the alumina microchannel part.