南京航空航天大学学报2025，Vol.57Issue(4)：610-619,10.DOI:10.16356/j.1005-2615.2025.04.003
试样构型与标距对SiCf/SiC复合材料拉伸性能的影响
Influence of Specimen Geometry and Gauge Length on Tensile Properties of SiCf/SiC Composites
摘要
Abstract
To investigate the influence of specimen geometry and gauge length on the tensile properties of SiCf/SiC composites,specimens are cut from the same plate:dog-bone-shaped specimens(Type A)and Y-tabbed specimens with two gauge lengths(Types B and C).Room-temperature tensile tests are performed.Digital image correlation(DIC)is used to analyze damage evolution,and fracture characteristics are examined to thoroughly investigate the effects of specimen configuration and gauge length on tensile test results.It is found that specimen geometry and gauge length have a minor influence on the linear segment of the tensile stress-strain curve.However,the geometry significantly affects the ultimate tensile strength and fracture strain.Type A specimens,employing flat clamping,introduce an additional bending moment during loading,resulting in significantly lower ultimate tensile strength and fracture strain compared with Types B and C specimens,which use Y-tabbed suspension gripping.The difference in tensile properties between specimens with gauge lengths of 25 mm(Type B)and 15 mm(Type C)is less than 9％.This confirms that the size effect can be neglected when the gauge length exceeds 10 times the characteristic length(Lc=0.49 mm). The study demonstrates that Y-tabbed suspension specimens enable accurate determination of the material's true properties,and a gauge length greater than 5 mm can eliminate the influence of the size effect for the present SiCf/SiC composites. This research provides experimental evidence and theoretical support for the performance evaluation of aero-engine hot-section components and the design of specimens for in-situ sampling.关键词
SiCf/SiC复合材料/拉伸性能/试样构型/标距/夹持方式/本体取样Key words
SiCf/SiC composites/tensile properties/specimen configuration/gauge length/clamping method/in-situ sampling分类
航空航天引用本文复制引用
王雅娜,王振宇,赵文青,李天山,焦健..试样构型与标距对SiCf/SiC复合材料拉伸性能的影响[J].南京航空航天大学学报,2025,57(4):610-619,10.基金项目
稳定支持项目(2019-363). （2019-363）
