Thermoforming with Integrated Design Elements

在热成型过程中，热塑性片材被成型为三维部件。成型过程通常使用单侧工具通过施加压力差（真空和/或压缩空气）和/或借助于拉伸助剂来进行。热成型通常用于生产包装制品，但也用于生产技术部件。因此，热成型工艺仍然与注塑成型竞争。然而，与注塑成型相比，热成型仍然具有一些缺点。与注塑成型相比，热成型工艺的设计自由度有限。通过热成型工艺，只能生产没有功能元件（如肋、螺钉凸台、卡扣）的壳形零件。功能元件只能通过进一步的加工步骤（例如焊接或胶合）来附接。然而，一个新的研究项目，热成型与集成的设计元素，使得有可能将功能元素集成到热成型过程中。通过这种过程集成，可以节省连接设计元素的后续步骤。在使用集成设计元素的热成型过程中，首先必须将嵌件放置在模具中。之后，可以形成片材，并且同时将片材焊接到插入件。这就在嵌件和热塑性塑料板之间建立了一个紧密的连接。在这个研究项目中，必须研究热成型过程中与集成设计元素的基本材料关系。这将有助于理解这个新的过程。根据这些调查结果，还将开发一个流程模型。本研究计画的目的是探讨热成形制程中个别制程参数及其对焊缝品质的影响，并整合设计元素。此外，研究结果还可用于检验和改进现有的描述焊接过程作用机理的模型。

During the thermoforming process thermoplastic sheets are formed into three-dimensional parts. The forming process is usually carried out using a one-sided tool by applying pressure differences (vacuum and/or compressed air) and/or by means of stretching aids. Thermoforming is usually used to produce packaging articles but also for producing technical components. Therefore, the thermoforming process stays in competition with injection molding. However, thermoforming still has some disadvantages compared to injection molding. In comparison to injection molding, the freedom of design in the thermoforming process is limited. With the thermoforming process only shell-shaped parts without functional elements (e.g. ribs, screw bosses, snap-fits) can be produced. Functional elements can only be attached by a further processing step, such as welding or gluing. Nevertheless, a new research project, thermoforming with integrated design elements, makes it possible to integrate functional elements into the thermoforming process. Through this process integration, the subsequent step of joining design elements can be saved. During thermoforming with integrated design elements, first an insert must be placed in the mold. Afterwards the sheet can be formed and at the same time welded to the insert. This creates a cohesive connection between the insert and the thermoplastic sheet.Within this research project, the basic material relationships for the thermoforming process with integrated design elements have to be investigated. This will help to understand this new process. Based on these findings, a process modeling will also be developed. The aim of this research pro-ject is to investigate the individual process parameters and influences on the quality of the welded seam during thermoforming with integrated design elements. In addition, the results have to be used to check and enhance existing models for describing the acting mechanisms of welding processes.