Ti(C,N)基金属陶瓷是一种具有优异高温力学性能的功能结构材料，是传统硬质合金的首选替代产品，目前，其在机械切削加工、航空航天、地质勘探、石油化工、汽车零部件等领域均有应用。但是，Ti(C,N)基金属陶瓷强度和韧性不足的缺点，严重制约了其在更大范围内的进一步应用推广。因此，Ti(C,N)基金属陶瓷的强韧化性能研究成为国内外科研工作者们研究的重点。目前，研究者们主要通过优化原料配方、细化原料颗粒、改进生产工艺等方法对Ti(C,N)基金属陶瓷的强度和韧性进行改善。但是，对于纤维增韧Ti(C,N)基金属陶瓷的研究，至今未见任何相关报道。鉴于此，本文对短纤维/Ti(C,N)基金属陶瓷显微组织和力学性能进行研究。 首先，研究了碳纤维添加量对Ti(C,N)基金属陶瓷显微组织和力学性能的影响。结果表明，随着碳纤维添加量的增加，Ti(C,N)基金属陶瓷材料的断面层次感增强，断口处露出纤维数量逐渐增多，材料断裂机制主要表现为微裂纹偏转、纤维脱粘、纤维拔出、纤维断裂和纤维桥联，材料密度逐渐降低，孔隙率变大，材料抗弯强度呈现先升高后降低的趋势，当碳纤维添加量为4wt%时，材料整体力学性能达到最佳，材料硬度为12.25 GPa，抗弯强度为446.37 MPa，相对于未添加碳纤维的Ti(C,N)基金属陶瓷提高了9.3%，说明添加适量碳纤维可以改善Ti(C,N)基金属陶瓷的强度和韧性。 其次，研究了碳纤维表面改性、纤维镀层厚度和改性纤维球磨时间对Ti(C,N)基金属陶瓷显微组织和力学性能的影响。结果表明，添加表面改性碳纤维可以大大改善纤维与基体之间的相容性，进而改善材料整体性能，但是，纤维镀层过厚时，材料基体内孔隙率过高，缺陷数量增多，材料力学性能下降，同时随着球磨时间的延长，添加纤维尺寸不断变小，材料性能不断降低，当纤维厚度为1 μm、球磨时间为0.5 h时，既可大大改善纤维与基体间的相容性又可控制材料内部孔隙率不致过高。 最后，研究了氧化铝纤维添加量对Ti(C,N)基金属陶瓷显微组织和力学性能的影响。结果表明，材料密度和孔隙率在纤维添加量较低时变化不大，随着纤维含量的进一步增加，材料抗弯强度呈现先升高后降低的趋势，当氧化铝纤维添加量为6wt%时，材料整体力学性能达到最佳。

Ti(C,N)-based cermets are functional structure materials with excellent high temperature mechanical properties. Ti(C,N)-based cermets would be the preferred alternative products for traditional cemented carbides, and they are widely used in the mechanical machining, aerospace, geological exploration, petroleum chemical industry, auto parts and other fields. However, the shortage of the strength and toughness of the Ti(C,N)-based cermets strongly limits the wider application. Therefore, the toughness and strength improvement of Ti(C,N)-based cermets has become the focus of the domestic and foreign researches. At present, the researches of the toughness and strength improvement are mainly concentrated on optimization formulation of raw materials, refine of raw material particles and improving production technology and other methods However, the research of the fiber reinforced Ti(C,N)-based cermets has seldom reported up to now. In view of this, this study explores the feasibility and the effect of the added toughened fiber on the microstructure and mechanical properties of the Ti(C,N)-based cermets. Firstly, the effect of carbon fiber content on the microstructure and mechanical properties of the Ti(C,N)-based cermets were studied. The results showed that, with the increase of carbon fiber content, the sense of hierarchy at the fracture section was enhanced and the number of the exposing fiber gradually increased. The main micro-fracture mechanism of Ti(C,N)-based cermets were concluded as crack deflection, fiber debonding, fiber pullout, fiber fracture and fiber bridging. The density and the porosity of Ti(C,N)-based cermets decreased and increased, respectively. While the flexural strength of the cermets increased firstly and then decreased. When the carbon fiber content was 4wt%, the cermets achieved the best comprehensive mechanical properties, with the hardness of 12.25 GPa, the bending strength of 446.37 MPa which was increased by 9.3% when compared with the Ti(C,N)-based cermet without carbon fiber, indicating that the addition of appropriate amount of carbon fiber can improve the strength and toughness Ti(C,N)-based cermets. Secondly, the influence of carbon fiber surface modification, fiber coating thickness and the ball milling time of the modified fiber on microstructure and mechanical properties of the Ti(C,N)-based cermets were investigated separately. The results showed that the surface modification of carbon fibers can greatly improve the compatibility between the fiber and Ti(C,N) matrix, and thus could improve the overall performance of the cermets. Whereas, when the fiber coating was too thick, the porosity of the matrix became higher, and the defects became obvious, and finally the mechanical properties of materials decreased. On the other hand, the add fiber size became small, and thus the properties of the materials will be reduced, with the increasing ball milling time. The final conclusion was, the compatibility between the fiber and the matrix can greatly improve, and the controlled low porosity was obtained, when the thickness of the fiber was 1 μm, with ball milling time of 0.5 h. Lastly, the effect of the content of alumina fiber on the microstructure and mechanical properties of the Ti(C,N)-based cermets was studied. The results showed that, The density and porosity of the cermets changed slightly when the content of the added fiber was low. The flexural strength showed a trend of first increased and then decreased, with the further increase in the fiber content. When the amount of alumina fiber was 6wt%, the overall mechanical properties of the cermets reached the best.