Mechanical joining of dissimilar materials by shear clinching processes without pre-punching (shear clinching)

通过剪切铆接工艺机械连接异种材料，无需预冲孔（剪切铆接）

• 批准号: 227633773
• 负责人: Professorin Dr.-Ing. Marion Merklein
• 金额: --
• 依托单位: Laboratorium für Werkstoff- und Fügetechnik (LWF)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/227633773?language=en
• 关键词: Mechanical; joining; dissimilar; materials; shear

Political and environmental requirements demand the use of adapted materials in modern lightweight design structures. Joining these dissimilar materials challenges the development and advancement of existing technologies. Great potential offers the innovative shear-clinching technology which is investigated in this project. The single-stage process offers the opportunity to join material combinations with significantly different material properties without additional joining elements or pre-holing and retrieval of this pre-hole. The combined inner- and outer punch initialize a cutting operation in the die-sided brittle material as well as a drawing process in the punch-sided ductile joining partner for creating a form- and force-fitting joint. This reduces the required process time and avoids possible positioning errors that occur during multi-stage processes. The third funding phase focuses on investigating and improving the robustness of the shear-clinching process and the predictability of the properties of a shear-clinched joint. Therefore, three key research areas are set.To evaluate the tool-related design, the active elements are analyzed in terms of tool wear and the resistance of the tool materials. In addition to the identification of the process limits, the influence of process and batch-related deviations on the quality of the joint formation and the tool wear are examined. Based on these results the tool elements are adjusted for high local stresses and wear tests are carried out. The second focus is the evaluation of the process design. For this purpose, the previously analyzed single-element samples are replaced by multi-element samples to examine the influence of neighboring points on joint formation. An essential approach is identifying the influence of the radial material flow on the characteristic joint properties and set limits of a robust joining process. The influences on the joint formation of joint distance, sheet thickness and additional process based deviations are analyzed. Multi-element samples of the described material combinations are tested concerning joint strength and corrosive behavior.The final research topic is the review of the shear-clinching process regarding process safety and tested material combinations. Therefore, the findings from the first two phases of the project are combined with the tool- and process-sided results and evaluated in terms of process reliability. In particular, the failure modes of the joints are taken into account for enabling a prediction of the joint properties. The transferability of these findings will be evaluated by arranging different punch-sided aluminium alloys. The project is finalized with the summary of the results and a holistic review of the shear-clinching process.

政治和环境要求要求在现代轻质设计结构中使用合适的材料。连接这些不同的材料对现有技术的发展和进步提出了挑战。本项目研究的创新剪切铆接技术具有巨大的潜力。单阶段工艺提供了连接具有显着不同材料特性的材料组合的机会，而无需额外的连接元件或预钻孔和恢复该预孔。组合的内冲头和外冲头在模具侧脆性材料中启动切割操作，并在冲头侧延性连接伙伴中启动拉拔过程，以创建形状和力配合接头。这减少了所需的加工时间，并避免了多阶段过程中可能出现的定位错误。第三阶段的资助重点是研究和提高剪切铆接工艺的稳健性以及剪切铆接接头性能的可预测性。因此，设置了三个重点研究领域。为了评估刀具相关设计，从刀具磨损和刀具材料的阻力方面分析了活性元素。除了确定工艺限制之外，还检查了工艺和批次相关偏差对接头形成质量和工具磨损的影响。根据这些结果，调整工具元件以适应高局部应力，并进行磨损测试。第二个重点是流程设计的评估。为此，将先前分析的单元素样本替换为多元素样本，以检查相邻点对接头形成的影响。一个重要的方法是确定径向材料流对接头特性的影响，并设定稳健连接过程的限制。分析了接头距离、板材厚度和附加工艺偏差对接头形成的影响。对所述材料组合的多元素样品进行了有关接头强度和腐蚀行为的测试。最后的研究主题是对剪切铆接工艺有关过程安全性和测试材料组合的审查。因此，项目前两个阶段的研究结果与工具和流程方面的结果相结合，并根据流程可靠性进行了评估。特别是，考虑接头的失效模式以实现接头特性的预测。这些发现的可转移性将通过排列不同的冲孔铝合金来评估。该项目通过结果总结和剪切铆接过程的整体审查而最终确定。