Research on the bending and tensile mechanical properties of ceramic yarns

Abstract

Ceramic yarns play an important role in the aerospace sector, aviation, military, shipbuilding and nuclear industry, they have some advantages of high-temperature resistance, high specific strength and high specific modulus. However, almost no one studies the bending properties of ceramic yarns. To explore the influence of the degree of bending of ceramic yarn on its mechanical properties, three kinds of ceramic yarns (silicon carbide, silicon nitride and alumina) were knotting, bending and checking tensile tests. The retention rate of silicon nitride yarn after bending, checking and knotting tensile tests was 81.9%, 3.39% and 0.17%. The retention rate of silicon carbide yarn after bending, checking and knotting tensile tests was 95.1%, 4.88% and 0.09%, respectively. After bending, checking and knotting tensile tests, the fracture strength retention rate of alumina yarn was 91.8%, 0.39% and 0.04%. It was proved that the retention rate of breaking strength of ceramic yarn decreases seriously under different forms of bending. As a result, ceramic yarns should not be used under bending conditions.