Evaluation of new spot variant approach for joining of dissimilar materials

Abstract

Lightweight structures are typically applied in structurally optimized components integrating multi-lightweight materials. One major limitation for further development and wider use of these structures is the difficulty to join the materials with significant dissimilar physical properties, especially metals to polymeric based materials. The joining of metal to polymer is one important demand from modern mechanical design that still strives to find reliable and energy efficient manufacturing solutions for this field of application. The existing solutions are not able to meet all the demands, namely regarding load-bearing structures where thicker components are needed. In this scenario, a new solution for hybrid joining of advanced lightweight engineering material, was recently invented at Aalto University, and it will be tested in the variant of spot joining. The new solution envisages the joining of thick structural components enabling multi-directional mechanical resistance.

The current work aims to evaluate a new approach for the spot variant and to understand the process better. New laboratorial conditions were developed for the implementation of the joining method. Tentative work started with some slot variant tests, but focus was put on the spot variant. The results obtained from the mechanical testing of the spot variant indicate a 50 percent and 85 percent increase in the tensile shear and cross tension tests respectively.