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The papers using thermal analysis (DSC), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and other experimental means systematically studied the Mo 2 FeB 2 the cermets ingredients, the preparation process, the microstructure and mechanical properties. First summarized Mo 2 of FeB 2 cermets Development Overview and research progress, summarizes the of of Mo 2 of FeB 2 cermets sintering mechanism as well as the preparation process and composition of Mo 2 of FeB 2 Fund is a ceramic microstructure and properties of impact; briefly grain growth inhibitors in role in the preparation of fine grain metal ceramic; briefly SiC Whisker Composites progress; and on this basis that the purpose and significance of this research. First, the sintering temperature, sintering time, heating rate of liquid phase sintering stage of the cermet organization and performance. To draw the following experimental results: L1 stage 1 ° C / min the L2 stage using a heating rate of 5 ℃ / min and sintered at 1250 ℃ 40min cermet even, high density, fine grain size, has good mechanical properties . Cold isostatic pressing of the cermet organization and performance. The experimental results show that: after cold isostatic pressing of the sample sintered homogeneous, the average grain size is small and the grain size distribution is narrow, has a higher bending strength than the room temperature molded specimen. Studied the influence of the chemical composition on the metal ceramic microstructure and properties, the following conclusions: on the addition of 0.5 wt.% C, not only can be more completely eliminate the oxygen in the sintered body, but not the residual graphite and generate other brittle phases, the metal ceramics have better mechanical properties; interface Mn added to improve wettability. With the increase in the amount of Mn added, the grain continuing refinement, flexural strength increases, while the hardness is added in an amount of 5 wt.% The highest 90.7HRA. VFe added reduces the adhesive relatively hard phase in the wettability, but at the same time reduces the solubility of the hard phase in the bonding phase, inhibit the process of dissolution and precipitation, resulting in grain refinement. The VFe dosage 4.86 wt.%, The fine grain size, has the best mechanical properties, the flexural strength of 2350MPa hardness 90.6HRA. Study the impact on the the cermet organization and performance of three grain growth inhibitors and SiC whiskers, and draw the following conclusions: Join Cr3C2, VC metal ceramic grain refining effect is not obvious, adding TiC hard mass relative aggregation, increased porosity, and poor mechanical properties; addition of 0.5 wt.% SiC whiskers, cermet fine grain, homogeneous, have a high flexural strength, hardness and fracture toughness. With the increase of the whiskers added in an amount, the reduced wettability of the interface, the porosity increases, the mechanical properties dramatically reduced. After FeMo alloy part instead of Mo and Fe of cermet organization and performance, the following conclusions: the new alloy system tissue is uniform, the average grain size, the performance of the original alloy system quite. FeMo alloy part instead Mo and Fe Preparation of Mo , 2 of FeB 2 Fund cermets is feasible.
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