20.500.12556/RUL-154581 Karakterizacija mehanskih lastnosti 3D struktur sendvič plošč pri udarni obremenitvi Characterization of mechanical properties for 3D structures of a sandwich panel at impact loading Pri oblikovanju nosilnih konstrukcij razvoj stremi k čim bolj učinkovitemu razmerju med prostornino, maso in nosilnostjo struktur, tako na makro kot mikro nivoju. Sendvič plošče so eden izmed pogostih načinov uporabe nosilnih struktur za najrazličnejše aplikacije. Dober primer uporabe predstavljata letalska in avtomobilska industrija. Izdelki, ki so narejeni na tak način, so lahko med svojim delovanjem podvrženi najrazličnejšim obremenitvam. To so lahko upogib, torzija, trki in seveda njihove kombinacije, vse to ob najrazličnejših pogojih. Nove strukture je pred uporabo v industriji treba preizkusiti. Eden izmed načinov je tudi udarno testiranje, s katerim obravnavamo obnašanje določene strukture pri hipni obremenitvi. V magistrskem delu se raziskuje odpornost treh različnih meta-struktur na tlačno, strižno in udarno obremenitev. Preizkušalo se je triheksagonalno, giroidno in strukturo peščene ure. Pri tem se je uporabljalo metodo ciljnega nalaganja polimernega filamenta. Uporabljeni material je termoplast PLA. Vsi kosi so bili izdelani na Fakulteti za strojništvo, Univerze v Ljubljani. Pri udarnih preizkusih, ki so predstavljali jedro naloge, smo uporabljali pnevmatski top, s katerim smo v preizkušance streljali jeklene kroglice premera cca. 14 mm. Ugotovljeno je bilo, da je struktura peščene ure najučinkovitejša izmed preizkušanih treh. To smo potrdili tako z eksperimentalnim delom, kot tudi s simulacijami. V koncu naloge so predstavljeni tudi predlogi za nadaljnje delo. 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. meta-materiali dodajne tehnologije sendvič plošča notranja struktura udarna obremenitev pnevmatski top eksperimenti simulacije meta-materials additive manufacturing sandwich panel inner supportive structure shock load pneumatic cannon experiments simulations true false false [D. Lavrič] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2024-02-22 08:30:25 2024-02-22 08:30:34 2024-02-28 14:26:21 0000-00-00 00:00:00 2024 0 Ljubljana 0 XXII, 86 str. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.79:678.7:620.176.5(043.2) 259948 187103235 32835.pdf 32835.pdf 1 B5D0962867F9085D62DA4952747BD45F 8e4f748c2e69bc5fe170fca915dc911894e1e0c1efb2353ebb467468f3a21f57 45deac40-d154-11ee-bea9-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=181088 Fakulteta za strojništvo 0 0 0