Direct joining metal-plastic
Development of processes for the rapid thermal direct joining of metal-plastic hybrid joints in lightweight construction applications
Project duration
From: 01.04.2021 To: 30.09.2023Description
The aim of the TheDi project was to enable the production of high-strength metal-plastic hybrid joints within a few seconds using fast joining technologies and suitable pre-treatment methods. The required pre-treatments were implemented using technical methods suitable for serial production. Furthermore, it was demonstrated that resulting hybrid compounds can be separated by type using suitable technical means to enable reuse or recycling.
For this purpose, the metal surfaces were topologically pre-treated prior to joining. Laser structuring proved to be the most effective method for ensuring the high-strength mechanical properties of the joint. A structuring strategy to generate undercuts had a clear positive influence on the joint strength. As expected, joints with PA66 showed higher bond strengths than those with PP. This can be attributed to the higher base material strength of PA66. The glass fiber reinforcement of the plastic was also investigated. The joining process was mainly carried out using induction heating, with joining times of less than 15 seconds being achieved.
The evaluation of the joint was carried out using destructive tests, among others. In addition to the initial test, accelerated ageing tests were also carried out using a climate change test and salt spray test. No significant influence of ageing on the bond strength was found. This clearly indicates the high application potential for media-tight joints. A demonstrator for burst pressure testing and an LCA assessment of the joining process further demonstrated the promising performance of the joining process.
The IGF project 21456 BG of the FSKZ e.V. research association is funded by the Federal Ministry of Economics and Climate Protection (BMWK) via the German Federation of Industrial Research Associations (AiF) as part of the program for the promotion of joint industrial research (IGF) on the basis of a resolution of the German Bundestag.
The complete research results can be found in a comprehensive research report, which can be ordered from the SKZ.
