Fatigue of Smart Composite Metal Joints
Adhesive joints are ideal for connecting dissimilar materials in optimized structures.
Low weight and potential savings in manufacturing costs are major advantages related
to such joints, but their use is currently limited by uncertainties about the long-term
performance of the joints. A smart material with the ability to monitor its state of
health would be ideal for monitoring of the long-term performance and also for making
improvements to the joints. This thesis has explored the fatigue behavior of composite
metal joints and how optical fibers can be included in the joints as a method of integrated
Cracked IPE100 steel beams were repaired with composite patches. The fatigue life
of the patch repaired beams was tested in a four point bend test. Optical fibers were
embedded in the adhesive layer of the composite patch and on top of the patch. An
optical backscatter reflectometer was used to measure the strains in the composite metal
joint during testing. These measurements were compared against finite element analysis
and strain gauges. The results were found to coincide well with the finite element analysis
and the strain gauges. The optical fibers were proven to detect damage propagation and
growth versus number of cycles. It was observed that different failure modes propagating
in the composite metal joint could be detected and distinguished by the optical fibers.
Place, publisher, year, edition, pages
Institutt for produktutvikling og materialer , 2013. , 105 p.
IdentifiersURN: urn:nbn:no:ntnu:diva-22283Local ID: ntnudaim:9687OAI: oai:DiVA.org:ntnu-22283DiVA: diva2:648738
Echtermeyer, Andreas, Professor