冲击载荷作用下圆柱粘接接头强度控制参量及其影响规律研究

According to the extended application scope of adhesive joints in the high-tech fields, the prerequisite of the realization of the industrial applications reliably and economically is to master effective analysis and design methods. Due to the reality of that the researches of strength laws of the cylindrical adhesive joints under impact loadings are not yet conducted intensively, a V-type cylindrical adhesive joint is proposed as the research object in present project. The analyses of the failure strengths of the V-type cylindrical adhesive joints under the dynamic conditions are carried out via experiments methods and numerical calculations. Strength limit curve and related variable expression of the cylindrical adhesive joint are obtained, which is the key point should be focused on. In addition, the effect laws between the influential factors, such as strain rates and the sizes of cylindrical adhesive joints, and the control parameters in the strength expression are should be paid attention, which is used to master the relation between the influential factors and joint strengths/failure modes. Furthermore, the evaluations of the joint strengths and light-weight design methods are explored. The research results are hopeful to obtain the failure thresholds and mechanism of the cylindrical adhesive joint under dynamic conditions to widen the design concepts, which provide the tool of strength evaluation and the understanding of the laws for the applications of related technologies.

随着粘接接头在高技术领域中应用范围的扩大，掌握有效的分析设计方法是实现工程应用可靠性和经济性的基本前提。由于冲击加载条件下圆柱粘接接头的强度规律研究尚未深入开展，本项目以圆柱V形粘接接头为研究对象，采用实验与数值计算相结合的分析手段，开展其在冲击载荷作用下破坏强度的研究。重点是获取圆柱粘接接头的强度极限曲线及强度的量化表达式；并关注应变率及圆柱粘接接头尺寸等关键因素对强度表达式中各控制参量的影响规律，进而掌握关键因素与粘接强度及失效模式之间的内在联系，探索结构强度的评估与轻量化设计方法。研究成果有望获取动态条件下圆柱粘接接头的失效阈值与失效机理，拓宽粘接接头的设计思路，为相关技术的实际应用提供强度分析工具和规律认识。

本项目研究了圆柱V型轻质粘接结构在外载荷作用下的强度评估和损伤机理。主要研究内容包括三个方面：一是建立了能够表征粘接层开裂、扩展至完全失效渐进过程的等效模型，定量地描述了界面损伤程度，并通过量纲分析确定了影响结构峰值载荷的关键控制参量，进而着重分析了粘接剂类型、粘接层厚度及斜接角对粘接结构混合模式破坏的影响规律，得出I型、II型的内聚参数对粘接结构峰值载荷及破坏能的贡献不同，并由此推导出量化的关系表达式，且得出几何参数（粘接层厚度和斜接角）对粘接结构的峰值载荷及破坏能的影响是耦合的；二是发展了可控制粘接层厚度及斜接角的帽型圆柱试件制备方法，并搭建了改进的霍普金森压杆实验平台，实验获取了冲击压力波在不同粘接结构中的传播特性，得到了界面破坏模式的物理图像；三是基于考虑弹塑性变形及混合破坏模式的率相关内聚力模型，获得了圆柱V型粘接结构的强度极限曲线及强度的量化表达式，并得到了加载率与强度量化表达中控制参量的关系式，为结构的强度提供了一种有效的评估方法。通过上述三个方面的研究内容，在一定程度上阐明了关键因素与粘接强度及失效模式之间的内在联系，获得了圆柱粘接结构的失效阈值与失效机理。研究成果为轻质粘接结构强度的评估与轻量化设计方法提供了新的认识和基础支撑。本项目至今共发表学术论文9篇，其中SCI收录4篇，EI收录6篇。