Tensile fatigue behavior of plain-weave reinforced Cf/C–SiC composites. Issue 6 (1st May 2016)

• Record Type: Journal Article
• Authors: Li, Yang; Xiao, Peng; Li, Zhuan; Zhou, Wei; Liensdorf, Tom; Freudenberg, Wolfgang; Langhof, Nico; Krenkel, Walter
• Is Part Of: Ceramics international. Volume 42:Issue 6(2016)
• Page Start: 6850
• Page End: 6857
• Publication Date: 2016-05-01
• Subjects: C/C–SiC -- Tensile fatigue -- Matrix cracking -- Residual strength; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2016.01.068
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The fatigue behavior of plain-weave Cf /C–SiC composites prepared by liquid silicon infiltration (LSI) was studied under cyclic tensile stress at room temperature. The specimens were loaded with stress levels of 83% and 90% of the mean static tensile strength for 10 5 cycles. The cross-sections and fracture surfaces of the fatigued specimens were examined by optical microscopy (OM) and scanning electron microscopy (SEM), respectively. The results show that the specimens can withstand 10 5 fatigue cycles with a stress level of 90% of the static tensile strength. The retained strengths after fatigue for 10 5 cycles with stress levels of 83% and 90% are about 19% and 11% higher than the static tensile strength. Due to the observation of the microstructures a relief of the thermal residual stress (TRS) caused by stress-induced cracking is probably responsible for the enhancement. Furthermore, the fracture surfaces indicate that the fatigue stress results in interfacial debonding between the carbon fiber and matrix. Additionally, more single-fiber pull out was observed within the bundle segments of fatigued specimens.