Development and validation of a method to determine the frequency- and temperature-dependent stiffness and damping properties of plastics for the structure-borne noise simulation more precisely using the example of the for the ultrasonic welding process r

开发和验证一种方法，以确定塑料的与频率和温度相关的刚度和阻尼特性，以使用超声波焊接工艺的示例更精确地进行结构噪声模拟

• 批准号: 398244070
• 负责人: Professor Dr.-Ing. Christian Hopmann
• 金额: --
• 依托单位: Institut für Kunststoffverarbeitung (IKV) in Industrie und Handwerk an der RWTH Aachen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/398244070?language=en
• 关键词: Development; validation; method; determine; frequency

The ultrasonic welding has been established in the industry since the 1960s. Up to now, the design of the joining parts is usually based on the user experience. As well as the geometric design of the joining part bodies, which has to be suitable for welding, an appropriate component construction requires the consideration of constructive details, such as a process-specific design of the joining zone geometry. Additional functional elements or rib structures, which directly affect the structure-borne sound processes and thus the welding process, are often also to be taken into account. In general, extensive practical trials are necessary before the start of production.The component development also requires extensive practical trials for the determination of the welding parameters. In many cases, iterative elaborate and cost-intensive redesigns of the injection moulding tools arise to influence the sound propagation, so that a high-quality weld seam is achieved. The material analysis of the dynamic stiffness and damping behaviour of plastics is challenging due to the high frequencies of ultrasonic welding, and can only be carried out by means of iterative approaches. Realistic simulation of the acoustic structure interactions can be contributed to detect and avoid critical areas. However, input data are required, which precisely reflect the viscoelastic material behaviour of thermoplastic plastics.The aim of the research project is a further development of an alternative method, which is based on a reverse engineering process. This is supposed to determine mechanical characteristic values for an amorphous plastic (PMMA) and two semi-crystalline plastics (PP and PA), which allow a model description of the complex structure-borne sound processes in joining parts for the ultrasonic welding process, taking into account thermal influences.With the help of the research results, it is to be shown that the appropriate joining part design can already take place in the design phase. As a result, time and cost-intensive iterations in the development phase of complex joining parts will be omitted. Furthermore, a comprehensive basis for a better material and process understanding of the highly dynamic ultrasonic welding process and the sound propagation will be created.

自20世纪60年代以来，超声波焊接已在行业中确立。到目前为止，连接部件的设计通常基于用户体验。除了必须适合于焊接的连接部件主体的几何设计之外，适当的部件构造还需要考虑构造细节，例如连接区域几何形状的工艺特定设计。通常也要考虑附加的功能元件或肋结构，它们直接影响固体声过程，从而影响焊接过程。一般来说，在开始生产之前，需要进行大量的实际试验。部件开发也需要进行大量的实际试验，以确定焊接参数。在许多情况下，注塑模具的反复精心设计和成本密集型重新设计会影响声音传播，从而实现高质量的焊缝。由于超声波焊接的高频率，塑料动态刚度和阻尼行为的材料分析具有挑战性，并且只能通过迭代方法进行。声学结构相互作用的真实仿真可以有助于检测和避免关键区域。然而，需要输入数据，这些数据精确地反映了热塑性塑料的粘弹性材料行为。该研究项目的目的是进一步开发一种基于逆向工程过程的替代方法。这是为了确定非晶塑料（PMMA）和两种半结晶塑料的机械特性值（PP和PA），它允许在考虑热影响的情况下，对超声波焊接过程中连接部件的复杂结构声过程进行模型描述。借助研究结果，可以看出，在设计阶段就可以进行适当的连接部件设计。因此，在复杂连接部件的开发阶段中的时间和成本密集型迭代将被省略。此外，还将为更好地理解高动态超声波焊接过程和声音传播的材料和工艺奠定全面的基础。