不同温度环境下树脂基点阵复合材料夹芯结构有效力学性能评价及其破坏机理分析

Lattice core sandwich structures are new type structures with lightweight, high specific strength, specific stiffness and multifunctional structures. They have well application foreground in aviation and aerospace industry. Many results have been obtained for the produce and the mechanical properties investigation of composite lattice core sandwich structures at room temperature in the world. However, the evaluation of effective mechanical properties and the analysis of failure mechanism of three-dimensional composite lattice core sandwich structures at different temperatures are in underway stage. The perfect evaluation method and analysis instrument have not been built untill now. In this item, some composite core sandwich structure specimens will be designed and then will be produced according to engineering demand with considering the temperature effect factor using our ripe produce technology for three-dimensional composite lattice core sandwich structures. Its effective mechanical properties and analysis of failure mechanism at different temperatures are investigated. The main content of this item includes: the design and produce of three-dimensional resin matrix composite lattice core sandwich structures according to the integrative produce techniques; the effective mechanical properties and the failure mechanisms of three-dimensional resin matrix composite lattice core sandwich structures will be studied by using the combinative method of theory, numerical simulation and experiment, the effective mechanical properties of three-dimensional resin matrix composite lattice core sandwich structures will be accurately expressed and the failure criterion which exactly coincides with experiment results will also be given at different temperatures. These results will create the conditions for the application of this kind structure in aviation and aerospace industry.

点阵夹芯结构是一种新型的轻质高比强、高比刚多功能结构，在航空航天领域具有良好的应用前景。国际上对点阵复合材料夹芯结构的制备和常温下的力学性能研究较多，而对三维点阵复合材料夹芯结构在温度场作用下有效力学性能的评价及其破坏机理分析则处于起步阶段，还没有建立起较为有效的评价方法和分析手段。本项目将利用我们所具备的点阵复合材料夹芯结构制备技术，在考虑温度影响因素的条件下，根据工程需要设计并制备典型的实验件，研究其在不同温度条件下的有效力学性能及破坏机理。主要内容包括：结合一体化制备工艺，设计制备满足特定工程环境需求的树脂基三维点阵复合材料夹芯结构；理论、数值和试验相结合研究不同温度环境下三维点阵复合材料夹芯结构的有效力学性能和失效模式，在不同温度环境下得到正确反映树脂基三维点阵复合材料夹芯结构的有效力学性能及与试验相吻合的破坏准则，为此类结构在航空航天领域的应用创造条件。

碳纤维复合材料点阵夹芯结构由于具有轻量化和多功能化特点，因而在航空航天等领域具有广泛的应用前景。目前国内外学者对碳纤维复合材料点阵夹芯结构力学行为的研究主要集中在室温环境，很少有人研究温度对复合材料点阵夹芯结构力学行为的影响。因此，为了弥补这一不足有必要对其在不同温度环境下的力学行为展开研究，这将有助于复合材料点阵夹芯结构的设计与应用。本项目针对碳纤维和玻璃纤维复合材料点阵夹芯结构，设计和制备了碳纤维和玻璃纤维复合材料点阵夹芯结构,并对其在高低温环境下以及经高温热暴露处理后的力学行为进行了理论和实验研究，发表了一系列高水平的国际学术期刊论文，丰富了这一领域的研究方法和成果，具体成果如下：.1、建立了碳纤维复合材料直柱型和金字塔型点阵夹芯结构在不同温度环境下平压刚度和强度的理论预报公式，给出了温度对金字塔点阵夹芯结构侧压行为的影响规律；.2、给出了碳纤维复合材料金字塔点阵夹芯结构热暴露后的平压、剪切、侧压和弯曲性能理论预报公式，揭示了热暴露温度和热暴露时间对碳纤维复合材料金字塔点阵夹芯结构热暴露后的平压、剪切、侧压和弯曲失效机理；.3、确立了热暴露温度高低和冲击能量大小对金字塔点阵夹芯结构冲击响应的影响规律，揭示了点阵夹芯结构热暴露后的冲击失效机理和能量吸收特性。.4、通过实验给出了玻璃纤维复合材料金字塔型点阵夹芯结构在不同温度环境下平压强度，揭示了温度对金字塔点阵夹芯结构侧压行为的影响规律。.5、通过实验给出了高温环境对碳纤维复合材料金字塔点阵夹芯结构局部压陷行为和失效机制的影响机理，确立了碳纤维复合材料金字塔点阵夹芯结构在不同环境温度下的准静态压陷性能。