Experimental Study on Load-Bearing Property of 2D–C/SiC U-Beams
YANG Chengpeng1 , LI Jun2 , HE Zongbei3 , JIAO Guiqiong1
(1. Department of Engineering Mechanics, Northwestern Polytechnical University, Xi’an 710072, China; 2. AVIC China Helicopter Research and Development Institute, Jingdezhen 333001, China; 3. State Key Laboratory for Nuclear Fuel and Materials, Nuclear Power Institute of China, Chengdu 610213, China)
Load-bearing properties of typical ceramic matrix composite structures have rarely been studied. In this paper, the damage and fracture characteristics of 2D–C/SiC channel beams under bending-twist combined loadings were investigated experimentally. The load-bearing properties, damage process and failure mechanisms of the beam specimens were analyzed through strain monitoring and crack observation. It reveals that delamination and buckling are the main damage modes of 2D–C/SiC channel beam under complex loading, and the fracture process of the specimens is extremely complicated, accompanying with fluctuant and mutational strain response, meanwhile, its mechanical property is significantly degraded resulting in a low ultimate load carrying capacity. Comparing with intact specimen, the damage and fracture mechanism of the counterpart with open-hole is changed, and the delamination initiation and local buckling loads are obviously reduced.