Abstract

Depending on the specific additive manufacturing (AM) process the maximum size and complexity of AM components is restricted. Separation and subsequent joining can be an effective way of dealing with these issues. For joining of AM components adhesive bonding provides great potential for not constraining the joining partners geometry. This is only valid if the adhesive can still be applied to the connecting surfaces. This work investigates the effectiveness and applicability of additively manufactured inner channels to improve the adhesive application. The use case considered is a circular adhesive single lap joint (SLJ) between a laser powder bed fusion (PBF-LB) component made of AlSi10Mg and a cold drawn aluminum round bar. The SLJ´s were produced using different adhesive application concepts. Those can be implemented by realizing the joining partners geometry through AM processes, subtractive machining or without any machining. Subsequently the joints were subjected to static tensile tests. The fracture strength of joints where the adhesive was applied by injection into AM inner channels exceeds the fracture strength of joints where the adhesive was injected into geometries manufacturable by subtractive machining and exceeds the fracture strength of joints where the adhesive was pre-applied. Moreover, a stepwise de-powdering procedure for the inner channels was quantified by weighing methods and the resulting cross-sectional area of the inner channels was analyzed on the basis of microscopic images and digital image processing software.