RUAN Jieping, LIU Weiliang
(School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, China)
Abstract: TiB2 tapes were prepared by aqueous tape casting using TiB2 as hard layer, BNNTs as toughening phase of B4C base layer, Si powder as the sintering aids of B4C base layer, PEI as dispersant, CMC as binder and glycerinum as plasticizer. The influences of PEI content,CMC content, R value and solid content on the rheological properties of slurries were studied. The results indicated that TiB2 tape film of high quality could be prepared when the R value was 0.9, the content of PEI, CMC and solid content were 2wt.%, 5wt.% and 55wt.%, respectively.TiB2/B4C-BNNTs laminated ceramic composite was prepared by hot-pressing sintering through laminating the TiB2 tapes with the B4CBNNTs tapes pre-prepared by the different ratio of thickness of layers. The results showed when the ratio of thickness of base layer and hard layer was 1.8, the best mechanical properties of TiB2/B4C-BNNTs laminated ceramic composite were achieved when sintered at 2040 °C under 30 MPa for 30 min. The flexural strength and fracture toughness reached 598.63 MPa and 7.84 MPa·m1∕2, respectively.
Key words: TiB2/B4C-BNNTs; laminated ceramic composite; TiB2 aqueous tape casting; hot-pressing sintering