Properties and radiation effects in high-temperature pyrolyzed PIP-SiC/SiC

Abstract Polymer-derived silicon carbide has been regarded to be susceptible to radiation damage, because of severe radiation damage associated with radiation-induced crystallization of amorphous structure. However, recent advancement of highly heat-resistant silicon carbide fiber allows pyrolysis of matrix precursors at higher temperatures and expectedly the production of polymer impregnation and pyrolysis (PIP)–SiC/SiC composites with improved radiation resistance. In this work, characterization of microstructure, mechanical properties, and radiation stability of a developmental high-temperature pyrolyzed PIP–SiC/SiC composite was carried out. Although mechanical properties of Tyranno™-SA-reinforced composite pyrolyzed at 2023–2073 K were not very encouraging due to insufficient matrix densification, Tyranno-SA fiber appeared to retain its strength after repeated pyrolysis at temperatures ⩾2023 K. Carbon coating on the fiber fabric worked effectively as a fiber-matrix (F-M) interlayer in this system. Superior radiation stability was demonstrated by microstructural examination following dual-beam ion irradiation to 10 dpa at 873 K.