电场激活及压力辅助法制备AlMgB_(14)-TiB_2复合材料及性能表征

Preparation and Characterization of AlMgB_(14)-TiB_2 Composite by Field-activated and Pressure-assisted Synthesis

采用FAPAS法制备AlMgB14预反应粉,将其与TiB2粉混合,在烧结温度1500℃,轴向压力60 MPa,升温速度100℃/min、保温时间15 min条件下制备了具有较理想组织结构的AlMgB14-30wt%TiB2复合材料。通过HRTEM、SEM和EDS对AlMgB14-30wt%TiB2的微观结构进行表征,研究结果表明:AlMgB14-30wt%TiB2复合材料的显微硬度31.5 GPa,断裂韧性K1C值可达到3.65 MPa.m1/2,与机械合金化/单轴热压法制备的结果一致。并从微观结构分析了AlMgB14-TiB2复合材料的增韧机制主要来源于TiB2增强相与基体间形成高强结合界面。FAPAS法为AlMgB14基复合材料的制备开拓了低成本高效的新途径。

The pre-reacted AlMgB14 powders prepared by FAPAS were mixed with TiB2powers and then subjected to the temperature of 1500 ℃,the axial pressure of 60 MPa,the heating rate of 100 ℃ /min and dwelling time of 15 min.AlMgB14-30wt% TiB2 composites with ideal structures were successfully prepared.The microstructure and components of synthesized composites were observed and determined by scanning electron microscope（SEM）,energy dispersive X-ray analysis（EDX）,X-ray diffraction（XRD）,and transmission electron microscope（TEM）.The results show that the micro-hardness of the AlMgB14-30wt% TiB2 composites is 31.5 GPa and the fracture toughness K1C could reach 3.65 MPa.m1/2,which is consistent with those prepared by mechanical alloying/hot pressing.The microstructure analysis shows that the main toughening mechanisms of AlMgB14-TiB2composites are due to the hard phase dispersion strengthening,high-strength interface bonding.The FAPAS method might be used to synthesize AlMgB14-TiB2 composites at low costs with fast heating-up and efficiency.