中文摘要：

基于陶瓷/钛合金之间的熔化连接和原子互扩散，采用离心反应熔铸工艺成功制备出具有连续梯度特征的TiB2基陶瓷/Ti.6Al.4V合金层状复合材料。该复合材料分为陶瓷基体、中间过渡区及金属基底三层结构，且陶瓷/钛合金层间原位形成以陶瓷相(TiB2,TiC1.x)、Ti基合金相的尺寸和体积分数为特征的梯度纳米结构(微米.微纳米.纳米)复合界面。测试表明该复合材料层间剪切强度、弯曲强度、断裂韧性分别达到335MPa±35MPa、862MPa±45MPa和45MPa.m1/2±15MPa.m1/2。陶瓷/钛合金层间剪切断裂诱发TiB2、TiB棒晶的自增韧机制及有限的Ti基合金延性相增韧机制，使层间剪切测试与三点弯曲测试得出的载荷/位移曲线均呈现出近乎线性上升趋势。对TiB2基陶瓷、陶瓷/钛合金层状复合材料进行14.5军用制式穿甲弹DOP靶试，得出两种材料的平均防护系数分别为3.05和7.30。陶瓷/钛合金层间原位生成的梯度纳米结构复合界面不仅改善了陶瓷/钛合金之间声阻抗匹配，而且也使陶瓷/钛合金层间保持高的结合强度。陶瓷/钛合金层状复合材料遭受弹体冲击时，将诱发界面载荷传递与剪切耦合的双重效应，最终在表观上使陶瓷/钛合金层状复合材料的防弹性能得以显著提升。

英文摘要：

Based on fusion bonding and atomic inter-diffusion between the liquid ceramic and molten Ti-based alloy, the continuously-graded laminated composites of TiB2-based ceramic and Ti-6Al-4V alloy were prepared by SHS centrifugal casting. The laminated composites consist of three-layer structure with the ceramic matrix, the intermediate layer and the Ti-based alloy substrate,and, within the intermediate layer, a nano-structured continuously-graded (microstructured → micro/nanostructured → nanostructured) microstructures characterized by the size and distribution of TiB2,TiB and Ti-based phases were achieved. Interlaminar shear strength, flexural strength and fracturetoughness of the prepared composite were measured to be 335 MPa ± 35 MPa, 862 MPa ± 45MPaand 45 MPa?m1/2 ± 15 MPa?m1/2, respectively. FESEM fractographyies showed that, because of theachievement of self-toughening mechanism by TiB2 platelets and TiB rod-like grains along withlimited ductile toughening mechanism by Ti-based phases during interlaminar shear in the composite,two kinds of load-displacement curves resulting respectively from interlaminar shearing test and3-point bending test presented nearly the linear-increase trends. By conducting DOP test with 14.5mm army AP projectiles on TiB2-based ceramic and the laminated composite, the average ballisticmass effectiveness of two materials were measured to be 3.05 and 7.30, respectively. Hence, it wasconsidered that, because of the nano-structured graded composite interface in-situ developed from theceramic to Ti-6Al-4V alloy, the acoustic impedance matching was improved between the ceramicand the alloy, while high bonding strength was maintained in the laminated composite. As a result,the dual effects of load transferring and shear coupling by the interlaminar interface were initiated as the composite was impacted by the projectile, and high ballistic performance of the laminated composite was finally achieved.