Vpliv polnila na mehanske lastnosti 3D tiskanega termoplastičnega poliuretana

diplomsko delo

Katarina Kušar (Author), Tomaž Lampe (Reviewer), Andrijana Sever Škapin (Mentor)

Abstract

Uvod: Dodajalna tehnologija, imenovana tudi 3D tisk, je postala vsestranska tehnologija, ki omogoča izdelavo tridimenzionalnih predmetov z dodajanjem zaporednih plasti. Ena najpogosteje uporabljenih tehnologij 3D tiska je modeliranje s spajanjem slojev - tehnologija FDM. Postopek tiskanja ter kakovost in lastnosti natisnjenega predmeta so odvisne od velikega števila parametrov. Za mehanske lastnosti 3D tiskanega predmeta so najbolj pomembni parametri povezani s strukturo izdelka. Glavna parametra sta delež in vzorec polnila. Poleg parametrov tiskanja je pomembna tudi izbira primernega materiala. Danes je pri tehnologiji FDM na voljo veliko različnih materialov, kot so na primer akrilonitril butadien stiren (ABS), polimlečna kislina (PLA) in termoplastični poliuretan (TPU). Namen: Raziskati in analizirati povezavo med dvema dejavnikoma, deležem in vzorcem polnila, in mehanskimi lastnostmi 3D tiskanega predmeta ter ugotoviti optimalno kombinacijo deleža in vrste vzorca polnila, s katero je mogoče doseči najboljše mehanske lastnosti 3D tiskanega predmeta iz TPU. Metode dela: Uporabili smo preizkušance natisnjene s filamentom varioShore TPU, ki smo jih natisnili na 3D tiskalniku BlackBelt. Primerjali smo deleže polnila od 10 % do 100 % ter dva vzorca polnila, Gyroid in Zig Zag. Skupaj je bilo natisnjenih dvainpetdeset preizkušancev. Izvedli smo natezni in tlačni test ter merjenje trdote po Shore A v skladu z izbranimi standardi. Določili smo tlačno in natezno trdnost, Youngov modul in raztezek pri pretrgu oz. pri 20 % deformaciji v primeru tlačnega testa. Ovrednotili smo tudi ponovljivost meritev. Rezultati: Natezna trdnost pri obeh vzorcih polnila raste z naraščajočim deležem polnila do 70 % deleža polnila, z nadaljnjim povečevanjem deleža polnila trdnost ostaja konstantna. Enak trend naraščanja opazimo tudi pri Youngovem modulu in relativnem raztezku. Izmerjena trdota narašča le do približno 50 % deleža polnila, z nadaljnjim povečevanjem deleža polnila se trdota le malenkost spreminja. Največja izmerjena trdota je 70 po Shore A pri 100 % obeh vrst polnila, Zig Zag in Gyroid. Pri višjih deležih polnila zaznamo tudi večje vrednosti tlačne trdnosti. Pri tlačnem testu so vrednosti naraščale z deležem polnila do 90 % zapolnitve. Pri večini preizkušancev smo izmerili večje vrednosti preiskovanih mehanskih lastnosti pri uporabi vzorca polnila Zig Zag. Razprava in zaključek: Ugotovili smo, da tako delež kot tudi vzorec polnila pomembno vplivata na mehanske lastnosti 3D tiskanih predmetov. Višji deleži zapolnitve so zaradi gostejše notranje strukture na splošno privedli do večje natezne in tlačne trdnosti ter trdote. Vrsta polnila ni bistveno vplivala na trdoto. Pri preizkušancih s polnilom Zig Zag smo ugotovili večjo tlačno in natezno trdnost, kot pri tistih, kjer smo uporabili vzorec polnila Gyroid.

Keywords

diplomska dela;ortotika in protetika;aditivna tehnologija;3D tisk;modeliranje s spajanjem slojev (FDM);termoplastični poliuretan;mehanske lastnosti;vzorec polnila;delež polnila;

Data

Language:	Slovenian
Year of publishing:	2023
Typology:	2.11 - Undergraduate Thesis
Organization:	UL ZF - University College of Health Studies
Publisher:	[K. Kušar]
UDC:	617.3
COBISS:	166712835
Views:	9
Downloads:	1
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	ǂThe ǂeffect of the infill on mechanical properties of 3D printed thermoplastic polyurethane
Secondary abstract:	Introduction: Additive manufacturing, also known as 3D printing, has become a versatile technology that allows the production of three-dimensional objects by adding material layer by layer. One of the most commonly used 3D printing technology is fused deposition modelling - FDM. The printing process and the quality and properties of the printed object depend on a large number of parameters. For the mechanical properties of the 3D printed object, the most important parameters are related to the structure of the product. The main parameters are the infill percentage and pattern. In addition to the printing parameters, the choice of a suitable material is also important. Nowadays, many different materials are available for FDM technology, such as acrylonitrile butadiene styrene (ABS), polylactic acid (PLA) and thermoplastic polyurethane (TPU). Purpose: To investigate and analyze the connection between two factors, infill percentage and pattern, and the mechanical properties of a 3D printed object and to identify the optimal combination of infill proportion and pattern type that can achieve the best mechanical properties of 3D printed thermoplastic polyurethane. Methods: Test specimens were printed with varioShore TPU filament on a BlackBelt 3D printer. Infill percentages from 10% to 100% and two infill patterns, Gyroid and Zig Zag were compared. In total, fifty-two test specimens were printed. Tensile, compressive and Shore A hardness tests were carried out according to selected standards. Compressive and tensile strength, Young's modulus and elongation at break and at 20 % strain in the case of the compressive test were determined. The repeatability of the measurements was also evaluated. Results: The tensile strength of both infill patterns increased with increasing infill percentage up to 70% infill, the strength remained constant with a further increase in infill percentage. The same increasing trend was observed for Young's modulus and relative elongation. The measured hardness increased only up to about 50% of the infill, with only a slight change in hardness with further increases in the infill percentage. The maximum measured hardness was 70 Shore A at 100% for both Zig Zag and Gyroid. Higher compressive strength values were also observed at higher infill percentages. In the compressive test, the values increased with the proportion of filler up to 90% fill. For most specimens, higher values of the investigated mechanical properties were measured when using the Zig Zag infill pattern. Discussion and conclusion: We found that both infill percentage and pattern have a significant effect on the mechanical properties of 3D printed objects. Higher infill percentages generally led to higher tensile and compressive strength and hardness due to a denser internal structure. The infill pattern did not have a significant effect on hardness. The specimens with Zig Zag infill pattern showed higher tensile and compressive strength than those using the Gyroid pattern.
Secondary keywords:	diploma theses;orthotics and prosthetics;additive technology;3D printing;fused deposition modeling (FDM);thermoplastic polyurethane;mechanical properties;infill pattern;infill percentage;
Type (COBISS):	Bachelor thesis/paper
Study programme:	0
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. v Ljubljani, Zdravstvena fak., Oddelek za protetiko
Pages:	44 str., [7] str. pril.
ID:	20015644