采用B4C和FeSi2对C/SiC刹车材料改性的新方法及其摩擦磨损机理

盘/片刹车副在使用全C/SiC（碳陶）刹车材料时磨损大，摩擦系数不稳定，影响其在高速列车和汽车等盘/片刹车结构中应用推广。主要原因是碳陶刹车材料基体韧性差，盘/片摩擦界面在刹车过程中易产生脆性剥落，而且摩擦界面易产生氧化磨损加剧脆性剥落。本项目拟通过B4C浆料浸渗结合FeSi75熔融浸渗工艺（RMI-FeSi75）在碳陶刹车材料中引入韧性基体组元FeSi2和自愈合防氧化组元B4C，降低摩擦界面的氧化磨损和脆性剥落来改善材料的摩擦磨损性能。研究并揭示FeSi75熔渗反应机理及材料的摩擦组元微结构形成机理，B4C、FeSi2改性碳陶刹车材料的组成/结构对材料性能的影响规律，以及B4C、FeSi2改性碳陶刹车材料的摩擦磨损机理；并研究B4C、FeSi2改性碳陶刹车副材料的组成/结构/性能匹配设计。本项目将完善碳陶刹车材料的材料体系及工艺体系，丰富碳陶刹车材料的摩擦磨损机理，为其推广应用奠定基础。

Serious abrasion and friction coefficient instability of the disk/pad brake pairs were produced when the full C/SiC (carbon-ceramic) brake disk and pad were used, which affect carbon-ceramic brake materials applied to the disk/pad brake systems, such as the high-speed train and automobile brake systems. The main reason is that the poor matrix toughness of the carbon-ceramic brake materials will lead to the brittle flaking off of the disk/pad friction interface during braking, and the friction interface is easy to produce oxidation wear to aggravate the brittle flaking off. The project intends to introduce the toughness matrix FeSi2 and self-healing component B4C into the brake materials by B4C slurry infiltration combined with FeSi75 melt infiltration process that reduce the oxidation wear and brittle flaking off to improve the friction and wear properties of the materials. The infiltration and reaction mechanism of FeSi75 melt and the microstructure formation mechanism of the friction components, the influence of the composition and microstructure on the properties of the B4C and FeSi2 modified carbon-ceramic brake materials, and friction and wear mechanism of the brake materials will be researched and revealed. And the matching design among the composition, microstructure and properties of the B4C and FeSi2 modified carbon ceramic brake materials will be studied. The project will improve the material system and process system of carbon-ceramic brake materials, and enrich the tribological mechanism of carbon-ceramic brake materials. The results will promote the applications of carbon-ceramic brake materials.