Strength-optimal onsert shapes

The onsert is a joining element for local load introduction into fiber reinforced panels. It is bonded onto the surface of the otherwise unharmed substrate. This study examines strength limiting influences and searches for optimal shapes. The elements should be manufactured by metal injection moulding (MIM) which allows for complex geometries. The influence of the stiffness of the bonding partners is examined. A bending effect of the substrate is identified as strength critical. For the computational optimization a shape prototype is represented by a custom-tailored concept based on non-uniform rational B-splines (NURBS). The control points of this parameterization are adapted by an evolutionary algorithm in order to minimize a quality criterion. Candidate solutions are simulated by the finite element method (FEM). The capabilities of the method are illustrated in several numerical examples.