The concept of a strong interface applied to SiC/SiC composites with a BN interphase

Strong interfaces have been shown to allow improvement of the mechanical pr operties of ceramic matrix composites (CMC). The concept of a strong interf ace has been established in SiC/SiC composites with pyrocarbon (PyC) or mul tilayered (PyC/SiC) fiber coatings (also referred to as interphases). The p resent paper reports an attempt directed at applying the concept of a stron g interface to SiC/SiC composites with a BN coating (referred to as SiC/BN/ SiC). Fiber bonding and frictional sliding were investigated by means of pu sh-out tests performed on 2D-composites as well as on microcomposite sample s, and tensile tests performed on microcomposites. The stress-strain behavi or of the SiC/BN/SiC composites and microcomposites is discussed with respe ct to interface characteristics and location of debonding either in the coa ting or in the fiber/coating interface. (C) 2000 Acta Metallurgica Inc. Pub lished by Elsevier Science Ltd. All rights reserved.