以二硼化钛(TiB2)为硬夹层，硅(Si)粉为基体层碳化硼(B4C)的烧结助剂，氮化硼纳米管(BNNTs)为基体层的补强增韧剂，聚乙烯亚胺(PEI)为分散剂，羧甲基纤维素钠(CMC)为粘结剂，甘油为增塑剂，采用水基流延成型工艺制备TiB2流延膜。研究了分散剂含量、粘结剂含量、增塑剂与粘结剂质量比值(R值)以及固相含量对TiB2流延浆料流变性的影响。实验结果表明：当PEI含量为2wt.%，CMC含量为5wt.%，R值为0.9，固含量为55 wt.%时可制备出高质量的TiB2流延膜。与本实验室已制备的B4C-BNNTS流延膜以不同层厚比进行叠层、热压烧结制备出TiB2/B4C-BNNTs层状陶瓷复合材料。实验结果表明：当基体层与硬夹层的层厚比为1.8：1时，预制体于2040℃、30 MPa下热压烧结30 min制备的TiB2/B4C-BNNTs层状陶瓷复合材料的力学性能最佳，其抗弯强度和断裂韧性分别达到598.63 MPa和7.84 MPa·m1/2。%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 inlfuences of PEI content, CMC content, R value and solid content on the rheological properties of slurries were studied. The results indicated that TiB2 tape iflm 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 B4C-BNNTs 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 lfexural strength and fracture toughness reached 598.63 MPa and 7.84 MPa·m1∕2, respectively.
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