Ascher, Michael; Pang, Genny A.; Späth, Ralf. (2023). Method for the Design of Additively Manufactured Inner Channels intended for the Adhesive Application. CIRP Design Conference (33., 2023, Sydney).

Abstract

Joining of metal parts manufactured by laser beam powder bed fusion (PBF-LB/M) eliminates the inherent size restriction of this additive manufacturing process and reduces the manufacturing effort. Adhesive bonding presents great potential for joining of PBF-LB/M parts, as there are no constraints on the shape of the connecting surfaces, as long as the adhesive can be applied. The freedom of design underlying the PBF[1]LB/M process enables the construction of inner channels in the parts, which can facilitate the adhesive application. The adhesive can be injected into a single inlet on the exterior of a part and directed through inner channels before leaking from multiple outlets into the adhesive fill gap between the pre-aligned adherents. To avoid insufficient adhesive distribution and air inclusions in the adhesive fill gap, both of which reduce the bond strength, a methodical approach for the design of inner channels intended for adhesive application by injection is required. This work provides a corresponding design method based on the theory of fluid mechanics. Moreover, an example case of a PBF-LB/M sleeve to be joined to a circular tube is presented. Results from a CFD analysis show that the inner channels designed using the presented method lead to excellent coverage of the adhesive fill gap with adhesive and minimal air inclusions.

URL
https://doi.org/10.1016/j.procir.2023.02.164