C. Weddeling, S. Gies, N. Ben Khalifa, A.E. Tekkaya:
In: Journal on Manufacturing Science and Engineering, DOI: 10.1115/1.4030878


Modern lightweight concept structures are increasingly composed of several dissimilar materials. Due to the different material properties of the joining partners, conventional and widely used joining techniques often reach their technological limits when applied in the manufacturing of such multi-material structures. This leads to an increasing demand for appropriate joining technologies, like joining by die-less hydroforming (DHF) for connecting tubular workpieces. The present work introduces an analytical model to determine the achievable strength of form fit connections. This approach, taking into account the material parameters as well as thegroove and tube geometry, is based on a membrane analysis assuming constant wall thicknesses. Besides a fundamental understanding of the load transfer mechanism, this analytic approach allows a reliable joining zone design. To validate the model, experimental investigations using aluminum specimens are performed. A mean deviation between the calculated and the measured joint strength of about 19 % was found. This denotes a good suitability of the analytical approach for the design process of the joining zone.