SiC陶瓷纤维增韧SiC陶瓷基复合材料(SiCf/SiC)是新一代高温热结构部件的关键材料。增强体SiC纤维是制备高质量SiCf/SiC的关键。与第三代SiC纤维（拉伸强度约3GPa）比较，单晶SiC纳米纤维（SiCnf）具有直径小、强度高（拉伸强度约16GPa）的特点，且宏观呈现棉花絮状，可加工为无纺布/纸/毡状预制体。目前SiCnf主要通过在SiC陶瓷纤维或碳纤维表面原位生长的方式，作为第二增强体引入到陶瓷基体中，虽然有一定强韧化效果，但存在SiCnf体积含量小、致密度低和界面难以调控的问题，无法有效发挥SiCnf优异的力学性能。申请人拟在前期SiCnf规模化制备和SiC陶瓷制备的基础之上，开展基于高体积分数、致密SiCnf增强SiC的反应熔渗制备及反应机理和动力学研究，SiCnf与SiC基体的界面设计，研究SiCnf强化机制。研究可为SiC/SiC制备提供新的研究途径和策略。

SiC ceramic fiber-reinforced SiC matrix composite materials (SiCf/SiC) is a key materials for the new high temperature structural parts. SiC ceramic fiber reinforcement is the key element for the SiCf/SiC matrix composites. Compared with the third-generation continuous SiC ceramic fiber with a tensile strength of 3 GPa, the single-crystal SiC nanowires/nanofibers have small diameter, high tensile strength (16GPa) and super-plasticity. The preform of SiC nanowire nonwoven fabric and nanowire paper/mat can be fabricated by this kinds of cotton-like SiC nanofibers. SiC nanofibers were regarded as the assistant reinforcement of the matrix composite materials, which was fabricated by the in situ synthesis method on the surface of SiC ceramic fiber or carbon fiber. Although the SiC nanowire-contained SiC ceramic shows stronger and tougher performance, it cannot shows the excellent mechanical properties of SiC nanofibers because the low volume fraction, low compactness of SiC nanofibres and uncontrollable interface. Based on our previous research work on the large-scale fabrication of SiC nanofibers and the reactive melt infiltration of SiC ceramic, the SiCnf/SiC matrix composite materials with high volume fraction and high compactness of SiC nanofibres will be fabricated by the reactive melt infiltration method. The reaction mechanism and kinetics of Si/C will be investigated. The interface between SiCnf and SiC matrix will be designed. The strengthening-toughening mechanisms of the high volume fraction SiC nanofibres reinforced SiC matrix composites will be discussed. SiCnf/SiC will provide a new strategy toward materials design and fabrication for the research and development of the SiC/SiC composites.