Damage and fracture of a ceramic matrix composite under isothermal and thermomechanical fatigue loading

• Published in: Theoretical and applied fracture mechanics Vol. 95; pp. 218 - 232
• Main Author: Longbiao, Li
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.06.2018; Elsevier BV
• Subjects: Ceramic fibers; Ceramic matrix composites; Ceramic-matrix composites (CMCs); Crack propagation; Cyclic loads; Cyclic testing; Damage; Debonding; Fatigue failure; Fatigue tests; Fiber composites; Fracture; Fractures; Hysteresis loops; Interfacial shear stresses; Material properties; Shear stress; Sliding; Thermomechanical fatigue; Thermomechanical fatigue; Ceramic-matrix composites (CMCs); Fracture; Damage
• ISSN: 0167-8442; 1872-7638
• DOI: 10.1016/j.tafmec.2018.03.002

•The damage and fracture of long-fiber-reinforced ceramic-matrix composites (CMCs) under isothermal cyclic fatigue, dwell-fatigue and thermomechanical fatigue have been investigated.•The relationships between the cyclic temperature, cycle number, stress level, matrix multicracking, interface debonding/sliding and thermomechanical fatigue hysteresis loops have been established.•The damage evolution of fatigue hysteresis energy, peak strain, fatigue hysteresis modulus and interface debonding/sliding length versus cycle number under isothermal cyclic fatigue, dwell fatigue and thermomechanical fatigue loading have been compared.•The comparison analysis among cyclic fatigue, dwell-fatigue and thermomechanical fatigue loading have been conducted, and the effects of temperature and loading frequencies on damage and failure of CMCs have been discussed. In this paper, the damage and fracture of long-fiber-reinforced ceramic-matrix composites (CMCs) subjected to the isothermal cyclic fatigue, dwell-fatigue, and in-phase (IP) and out-of-phase (OP) thermomechanical fatigue (TMF) have been investigated. The fiber/matrix interface shear stress is determined as a function of testing temperature and material properties, which affects matrix multicracking and fiber/matrix interface debonding/sliding upon unloading/reloading. The relationships between the cyclic testing temperature, applied cycle number, fatigue peak stress level, matrix crack spacing, fiber/matrix interface debonding/sliding, and the shape, location and area of thermomechanical fatigue hysteresis loops have been established. The damage evolution of fatigue hysteresis dissipated energy, fatigue peak strain, fatigue hysteresis modulus and fiber/matrix interface debonding/sliding lengths versus applied cycle numbers subjected to isothermal cyclic fatigue, dwell-fatigue, IP/OP TMF cyclic loading have been compared. The damage and fracture of cross-ply SiC/MAS composite subject to different fatigue loading types have been predicted. The comparison analysis among the isothermal cyclic fatigue, dwell-fatigue with different hold-times, and IP/OP TMF loading have been conducted, and the effects of testing temperature and loading frequencies on fatigue damage and fracture of long-fiber-reinforced CMCs have been discussed.