中文摘要：

采用反应硼化烧结法制备了Mo_2FeB_2基金属陶瓷。使用扫描电镜（SEM）,X射线衍射仪（XRD）研究了固相硼化反应阶段800~1 010℃的升温速率对Mo_2FeB_2基金属陶瓷显微组织和力学性能的影响。研究结果表明：从800℃以不同的升温速率（1~9℃/min）升温升至1 010℃时,随着升温速率的升高,粘结相体积分数先增加后减少,硬质相平均晶粒尺寸和长径比逐渐减小,Mo_2FeB_2硬质相晶格常数a逐渐降低,c基本保持不变,硬质相形貌逐渐由长条状转变为近等轴状;随着升温速率的升高,金属陶瓷抗弯强度先升高后降低,硬度逐渐升高,断裂韧性逐渐降低。以5℃/min升温得到的金属陶瓷可获得较为均匀的显微组织,且具有较好的综合力学性能,其抗弯强度为2 367.5 MPa,硬度为88.2 HRA,断裂韧性为27.6 MPa·m~（1/2）。

英文摘要：

Mo2FeB2-based cermet was prepared by reaction boronizing sintering process. The effects of heating rate during solid reaction boronizing state sintering （800~1 010 ℃） on microstructure and mechanical properties of Mo2FeB2- based cermets were studied by using X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The results show that when heating up from 800 ℃ to 1 010 ℃ at different heating rates of 1~ 9 %/min, with the increase of the heating rate, the morphology of the hard phase gradually changes from elongated morphology to quasi-equiaxed shape, the volume fraction of the binder firstly increases and then decreases, the average grain size and length-diameter ratio of hard phase decrease gradually. Meanwhile, the lattice parameter a of the hard phase decreases gradually and the lattice parameter c keeps almost invariant. With the increase of the heating rate, the transverse rupture strength of the cermet firstly increases and then decreases, the hardness increases and the fracture toughness decreases gradually. Typically, the cermet has the best mechanical properties with TRS of 2 367.5 MPa, hardness of 88.2 HRA and fracture toughness of 27.6 MPa·m^1/2, which is characterized by homogeneous microstructure when the heating rate from 800 ℃ to 1 010 ℃ is 5 ℃/min.