In the design of load-bearing structures, the development objective is to design structures
with the most effective ratio between the volume, mass and load-bearing capacity, both at
the macro and micro level. Sandwich panels are one of the common ways of using loadbearing structures for a wide variety of applications. A good example of use is the aviation
and automotive industries. Products that are made in this way can be subjected to a wide
variety of loads during their operation. These can be bending loads, torsion, impact loading
and, of course, their combinations. New structures must be tested before being used in
industry. One of the methods is impact testing, which is used to examine the behaviour of a
certain structure under the impact load. In the master's thesis, the resistance of three different
meta-structures to compressive, shear and impact loads is investigated. Trihexagonal, gyroid
and hourglass structures were tested. The method of targeted loading of the polymer filament
was used. The material used was thermoplastic PLA. All pieces were manufactured at the
Faculty of Mechanical Engineering, University of Ljubljana. In the impact tests, which
represented the core of the task, a pneumatic gun was used to shoot steel balls with a diameter
of approx. 14 mm. The hourglass structure was found to be the most efficient of the three
tested. This was confirmed with experimental work and with simulations. Suggestions for
further work are also presented at the end of the assignment.
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