Work Package 2

The work in this WP will undertake design studies to optimise the load transfer at the interfacial region of dissimilar material joints. The results from WP1 will be used to provide quantitative information of the interfacial region mechanical properties. The service performance of the initial joint designs will be evaluated through characterisation tests in WP5 and where appropriate an iterative approach will be adopted whereby improvements in the design will be made in this WP to be re-evaluated in WP5.

Task 2.1 – Optimisation of matrix nanoparticle interaction for dissimilar metal joints

The development of a model will be performed which will simulate the progress of microstructure in the different characteristic zones. This model will describe the alteration of f (specific volume fraction) and r (radius) of the strengthening phase during the thermal cycle of the weld and it will predict the final values of these parameters.

The basic input data of the model will be the characteristics of the initial microstructure of the alloy and the thermal cycle for each point of computations.

Task 2.2 – Design optimisation of metal/composite joints

The design and optimization of the bonded joints proposed for the metal to composite joints will be carried out through finite element (FE) numerical simulations as mechanical/structural calculation tool.

The cohesive behaviours will be defined taking into account the different failure modes that can appear in this type of joints: adhesive, cohesive or through the composite substrate. In each case, the experimental characterizations required for these simulations will be also performed, which might include tests at material level (the adhesive or the substrates) and tests at joint level (single or double lap shear tests, peel or pull out tests and fracture-mechanic tests, considered in WP5). The joints will be analysed under static and dynamic loads (mainly fatigue), depending on the applications foreseen for each type of joint.