Papers by Author: Hai Jiao Yu

Abstract: CNTs/AlN ceramics were fabricated by hot-pressing and their bulk density, flexural strength, thermal conductivity were characterized. The microstructure was also investigated. The fracture surface were analyzed by SEM. TEM was used for analyzing the microstructure. It is found that the density, mechanic and thermal-conductivity properties markedly decreased as the CNTs reinforced AlN ceramic; through microstructure observation, the conglomeration of CNTs mostly exist among the AlN grain boundary, and the CNTs were scathed by the high temperature and pressure of the hot-pressing.

Abstract: The influence of the fiber/matrix interlayers on the mechanical properties of T800-HB fiber (a kind of carbon fiber) (the fibrous is three-dimensional four-directional braided) reinforced silicon carbide (SiC) matrix composites has been evaluated in this paper. The composites were fabricated through PIP process, and SiC layers were deposited as fiber/matrix interlayers by the isothermal CVD process. Fiber/matrix debonding and relatively long fiber pullouts were observed on the fracture surfaces. The mechanical properties were investigated using three-point bending test and single-edge notched beam test. The T800-HB/SiC composites exhibited high mechanical strength, and the flexural strength and fracture toughness were 511.5MPa and 20.8MPa•m1/2, respectively.