通过对薄壁高温合金蜂窝夹层结构XY面内进行拉伸、压缩宏观实验,并观测不同载荷形式下带有不同类型缺陷的试件的破坏模式和性能曲线,得到了结构在拉伸和压缩载荷下不同的破坏机理及不同缺陷对其力学性能的影响。研究结果表明,结构在XY面内拉伸时断裂均发生于缺陷附近区域且由缺陷尖端处开始扩展;而在XY面内压缩载荷作用下的失效模式主要分为结构屈曲和局部失稳,失效部位多发生在缺陷所在水平区域。结构屈曲为理想破坏模式,局部失稳导致结构抗压强度偏低。所获结论为结构的服役可靠性及其损伤容限体系的建立奠定了必要的实验基础。
Through coplanar tensile and compressive experiments of thin-walled super alloy honeycomb sandwich structure,failure modes and performance curves of test samples with different defects under tensile and compressive loading were obtained as well as the effect of these defects on the mechanical properties of the structure.The results show that fracture of the structure occurs in the vicinity of defects under coplanar tensile loading,which can be attributed to stress concentration of the regions near these defects.The failure modes of the structure under coplanar compressive loading include structural buckling and local which are induced by the initial defects.The structural buckling is a kind of ideal failure modes,but the local buckling can lead to the decrease of compressive strength of structure.The study can provide an experimental basis for improving the structural reliability and damage tolerance of the structure.