中文摘要：

采用真空热压烧结法制备两种成分的ZrB_2增强NbMo基复合材料：42.5%Nb＋42.5%Mo＋15%ZrB_2、42.5%Nb＋42.5%Mo＋10.5%ZrB~（2＋）4.5%SiC（体积分数）。烧结工艺为温度1600℃,轴向应力30 MPa,保护气体为氩气,保温时间分为1 h和2 h。使用扫描电子显微镜、能谱分析仪和X射线衍射仪分析材料的微观结构和相组成,使用显微维氏硬度计和液压式万能试验机检测材料的力学性能。研究发现,ZrB颗粒均匀分布于NbMo固溶体中,在添加SiC的样品中有SiC的剩余以及MoSi_2相的生成。与无陶瓷相添加的样品相比,添加陶瓷相的样品的抗压强度由1380.15 MPa提高至1974.17 MPa,屈服强度提高至1664.13 MPa,硬度提高3~5倍。保温时间越长,材料的抗压强度、屈服强度和硬度越高。复合材料强度和硬度提高是固溶强化以及ZrB和NbMo之间良好的界面结合力的结果。

英文摘要：

Zirconium boride reinforced NbMo-matrix composites with composition of 42.5%Nb＋42.5%Mo＋15%ZrB_2（vol%） and 42.5%Nb＋42.5%Mo＋10.5%ZrB~（2＋）4.5% SiC（vol%） were fabricated by hot-pressing under an uniaxial load of 30 MPa at 1600 oC in Ar atmosphere with holding time of 1 h and 2 h. The microstructure and phase composition were analyzed by SEM,EDS and XRD. The mechanical properties were measured by Micro Vickers and hydraulic universal tester. Results show that small ZrB particles are distributed uniformly in NbMo solid solution. Residual SiC and formed MoSi_2 are found in the samples with SiC. The compressive strength is improved to 1974.17 MPa from 1380.15 MPa of the NbM o solid solution. The yield stress is improved to 1664.13 MPa and the hardness is 3~5 times higher than that of NbM o. The longer holding time（2 h） leads to the higher strength,yield stress and hardness. The increase in strength and hardness of the composites is a consequence of the solid solution strengthening mechanism and the excellent interface bonding between ZrB and Nb-Mo solid solution.