Lightweight and high strength sheet metal such as aluminium alloy sheets are used in a variety of industrial applications. Due to the limited weldability of these materials, mechanical joining techniques such as clinching are of interest. The challenge in this regard is that conventional round clinch forming locally induces large plastic deformations which potentially cannot be accommodated by materials with limited ductility. Ductile damage models are used to predict the occurrence of bottom cracks during conventional round clinch forming of EN AW-6082 T6 sheet. It is shown that cracks in the bottom of a clinched joint and the final static strength of a single lap shear specimen can be numerically reproduced provided that the post-necking strain hardening behavior and damage behavior of the base material are properly identified. The observed bottom cracks did not have a detrimental effect on the static strength and fatigue life of single shear lap specimens. It is hypothesised that fatigue cracks in single shear lap tests initiate due to fretting.

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The paper shows experimental and numerical analyses of the clinching process of 6xxx series aluminum sheets in T6 condition and the self-pierce riveting process of an aluminum die casting. In the experimental investigations the damage behavior of the materials when using different tool parameters is analyzed. The focus of the numerical investigations is the damage prediction by a comparison of different damage criteria. Moreover, strength- and fatigue tests were carried out to investigate the influence of the joining process-induced damages on the strength properties of the joints

Additive manufacturing processes play a disruptive role in several industrial sectors. Among them, Wire Arc Additive Manufacturing (WAAM) is a very promising process for the production of large-scale steel components and structures. As a common characteristic of innovative technologies, this process requires additional research and experimental work in order to understand how its thermal cycles will modify the mechanical and metallurgical properties of the manufactured components. Considering the lack of literature on the properties of WAAM components from specific steel alloys, the present work proposes a benchmark evaluation of five different steel filler metals based on their mechanical properties and operational parameters when applied for additive manufacturing. The mechanical properties, such as the tensile strength, yield strength, elongation, Charpy impact toughness and hardness were evaluated together with operational parameters such as cost, printability, spatter and fume formation during manufacturing, defect-free printing and heat input. These were analysed in order to obtain a full evaluation and comparison of the five filler metals. The experimentally determined results of every abovementioned aspect were higher or similar to the values found in the literature for generic steel filler metals used in additive manufacturing. This means that a designer or welding engineer can select the WAAM steel filler metal for further testing based on the welding wire datasheet. Besides that, a comparison was performed between blocks manufactured by WAAM with some frequently used base metals, in plate format, confirming its applicability.