Ograniczanie wyników
Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 122

Liczba wyników na stronie
first rewind previous Strona / 7 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  PLA
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 7 next fast forward last
EN
The subject of the article is the influence of filament moisture on the quality of products manufactured using the additive method using the Fused Deposition Modelling (FDM) method. Three types of thermoplastic polymers were tested: ABS, PLA and PET-G. The polymers were stored in environments with different humidity. The moisture content of the filament was determined as the water content in the material expressed as a percentage by weight. To obtain the expected humidity of the samples, they were conditioned for 7 days in tightly closed containers with constant humidity of 40%, 60% and 80%. After the sample conditioning process was completed, they were removed from the container and subjected to further tests. The influence of filament humidity on selected properties of manufactured products is presented, such as: surface quality of the obtained samples, tensile strength and dimensional repeatability. To sum up, the method of storing the filament affects the moisture content of the filament. The humidity of the filament, in turn, affects the quality of products manufactured using the FDM method, including: on: mechanical properties, dimensional stability, Surface appearance. Therefore, it is important in what conditions the filament is stored before the production process begins
2
Content available remote Właściwości fizyczne mieszaniny polilaktyd/skrobia termoplastyczna
PL
Przedstawiono wyniki badań właściwości mieszaniny PLA/TPS. Granulki polilaktydu (PLA) i skrobi termoplastycznej (TPS) w proporcjach masowych 25, 50 i 75% mieszano w mieszalniku bębnowym, a następnie mieszano w stanie stopionym i formowano we wtryskarce ślimakowej. Próbki polimerów analizowano pod kątem udarności, twardości i nasiąkliwości. Mieszaniny PLA/TPS wykazywały istotnie większą udarność niż każdy z materiałów składowych z osobna. Udarność była nawet dwukrotnie większa, co wskazywało na występowanie zjawiska synergizmu.
EN
Polylactide (PLA) and thermoplastic starch (TPS) granules in mass proportions of 25, 50, 75% were mixed in a drum mixer, and then meltmixed and shaped using a screw injection molding machine. Polymer samples were analyzed for impact strength, hardness and water absorption. The PLA/TPS mixts. showed a significantly higher impact strength than each of the component materials separately. The impact strenght was even twice as high, which indicated the occurrence of the synergism phenomenon.
EN
The effect of nanocellulose (3 or 5 wt%) on the PLA properties was investigated. Moreover, the possibility of using such composites as an expansion joint material was considered. Nanocellulose was obtained from wastepaper by mechano-chemical treatment. The structure, impact strength, tensile strength of the composites and the adhesion to the cement were studied. It was observed that with the increasing nanocellulose content, the impact strength and tensile strength decreased because of weak interactions at the interface and formation of agglomerates.
PL
W pracy zbadano wpływ nanocelulozy (3 oraz 5% mas.) na właściwości PLA. Dodatkowo rozważono możliwość zastosowania tego typu kompozytów jako materiału dylatacyjnego. Nanocelulozę otrzymano z makulatury poprzez obróbkę mechano-chemiczną. Zbadano strukturę, udarność i wytrzymałość kompozytów na rozciąganie oraz adhezję do cementu. Zaobserwowano, że wraz ze wzrostem zawartości nanocelulozy udarność i wytrzymałość na rozciąganie zmniejszały się jako efekt słabych oddziaływań na granicy faz i tworzenia się aglomeratów.
EN
The article is a review of the literature on the use of polymers in medicine as biomaterials. Examples of the preparation of the most commonly used synthetic polymers in medicine, such as: polylactide (PLA), polyglycolide (PGA), polyhydrobutyrate (PHB), polycaprolactone (PCL) are described. The characteristics of ceramic materials: hydroxyapatite (HAp) and tricalcium phosphate (TCP) are also presented in terms of the use of synthetic biodegradable polymers as biofillers. The last part of article is devoted to the functional properties of composites based on PLA with the addition of HAp and TCP.
PL
Artykuł stanowi przegląd literatury dotyczący zastosowania polimerów w medycynie jako biomateriałów. Opisano przykłady otrzymywania najczęściej stosowanych syntetycznych polimerów w medycynie takich jak: polilaktyd (PLA), poliglikolid (PGA), polihydromaślan (PHB), polikaprolakton (PCL). Przedstawiono także charakterystykę materiałów ceramicznych: hydroksyapatytu (HAp) i trójfosforanu wapnia (TCP) pod kontem stosowania jako bionapełniacze syntetycznych biodegradowalnych polimerów. Ostatnia część artykułu jest poświęcona właściwościom użytkowym kompozytów na osnowie PLA z dodatkiem HAp i TCP.
EN
The correct manufacture of products using FDM printers is not an easy task, taking into account the value and repeatability of material properties. The properties of elements manufactured in this way depend on many factors, both technological and material. Poly(lactic acid) PLA is one of the most willingly used materials in additive techniques. It is sold in a very wide range of colours. This work was intended to answer the question of how the type of pigment affects the mechanical and thermal properties of products obtained from PLA. The correlation between the material properties and the structure of the material as well as the macroscopic structure of the product has also been investigated. The paper analyses the mechanical and thermal properties of products made of PLA filaments in 12 basic colours obtained from one supplier. Bending, impact strength, HDT and Vicat softening point tests were carried out. The percentage content of residues after calcination the samples was determined. Additional analysis (DSC) was performed to interpret the obtained tests results. They indicate that the mechanical properties differ significantly between different types of PLA with differences of up to 45%. Vicat softening point tests indicate differences of 5°C between the extreme values of these parameters. The DSC interpretive study did not clearly show the reasons for these differences in the properties of the filaments.
6
EN
Purpose This study focuses on determining the best possible structure of the orthosis made with FDM 3D printing technology. To produce the samples, a thermoplastic PLA material was selected that met the conditions of biodegradability, biocompatibility and non-toxicity. The samples produced were subjected to a tensile strength test and corrosion resistance. Design/methodology/approach Studies based on FEM analysis were carried out using the advanced engineering software CAE - Inventor. The samples were designed in the CAD system, while the G-Code path was generated using the PrusaSlicer 2.5.0 program dedicated to the Prusa i3 MK3S+ printer, which was used to create the models. Surface morphology observations of PLA were carried out with a Zeiss SUPRA 35 scanning electron microscope (SEM). The static tensile test was performed on the Zwick/Roell z100 device based on the PN-EN ISO 527:1 standard. Electrochemical corrosion tests were carried out using the Autolab PGSTAT302N Multi BA potentiostat in Ringer solution at a temperature of 37ºC. Findings The research allowed the appropriate structure of the orthosis made of PLA polymer material using 3D FDM printing technology. The static tensile test, SEM and corrosion tests confirmed the correct application of this material for the selected purpose. It was possible to determine that samples with holes of 10 mm had the highest strength properties. Due to the tensile tests, the average tensile strength of those samples was around 61 MPa. The corrosion parameters of PLA were determined using Tafel analysis. Research limitations/implications The research methodology proposed in work can be used to study other biomedical materials. The results presented can be the basis for further tests in order to search for the best orthopaedic stabiliser. Originality/value The innovative part of the article are three different versions of structures intended for making orthoses used in medicine.
7
Content available Post-processing in multi-material 3D printing
EN
Purpose This study aims to investigate the adhesion of combining two materials with different properties (PLA-TPU and TPU-PLA) printed in FFF (fused filament fabrication) with post-processing treatments. Design/methodology/approach The scope of the study includes making variants of samples and subjecting them to three different post-printing treatments. After processes, shear tests were conducted to determine the adhesion. Findings The post-printing treatment results in a stronger inter-material bond and increased adhesion strength; the best average shear strength results were achieved for annealing without acetone and for PLA/TPU samples for treatment in cold acetone vapour. Research limitations/implications In the study, adhesion was considered in the circular pattern of surface development. Practical implications Reinforcement of the biopolymer broadens the possibilities of using polylactide. Examples of applications include personalised printing items, where the elastomer will strengthen the polylactide. Originality/value These studies aim to promote the use and expand the possibilities of using PLA biopolymer. The strength properties of printouts from different materials are often insufficient, hence the proposal to use post-printing processing.
EN
Purpose The aim of this paper is to compare the mechanical properties of selected recycled thermoplastics against their equivalents made from new raw materials manufactured using the FDM/FFF additive method. Design/methodology/approach Two materials were tested: recycled polylactide (R-PLA) and recycled poly(ethylene terephthalate) with the addition of glycol (R-PETG). Reference materials are their equivalents made from new raw materials. Both types of materials are widely available on the market. In order to compare their mechanical properties and to check whether recycled materials do not differ in quality from their equivalents made from new raw materials, tensile strength tests were performed. In addition, the Vickers microhardness was measured, and the structure of printed samples using optical microscopy was observed. Findings The paper presents the results of the static tensile strength test of samples made by the FDM/FFF technology from the tested materials in accordance with the ISO-00527-2-2012 standard. The samples were manufactured at the average temperature recommended by the producer ±10°C. The results of tensile strength tests indicate that the samples printed at the average temperature show the best tensile strength for both methods of filament deposition. Research limitations/implications The recycled materials are not significantly different from the reference materials in terms of tensile strength, microhardness and structure. It is reasonable to test other polymeric materials further and check materials from several consecutive recycling cycles. Practical implications Closing the cycle of plastic used in 3D printing. The ability to quickly transform waste products, e.g. PET bottles, into filaments and reuse them to produce full-value products. Originality/value The paper presents the results of strength and microhardness tests as well as microscopic investigations of two recycled thermoplastics commonly used in the industry manufactured using the FDM/FFF technology against the background of reference materials made from new raw materials.
EN
The article presents the impact of individual settings of both 3D printers and software dedicated to the preparation of printouts. 3D printing methods are discussed. The individual methods and tools necessary for the implementation of 3D prints are described. Materials that are used in 3D printing technology are also discussed. In addition, the construction of printers on which the samples for the tests described in this work were prepared was discussed. The advantages and disadvantages of using individual slicers for 3D printing are presented. The obtained measurement results of samples made of polylactide (PLA) are presented. The work was summarized with final conclusions.
PL
W artykule przedstawiono wpływ poszczególnych ustawień zarówno drukarek 3D oraz oprogramowania dedykowanego do przygotowania wydruków. Omówiono metody druku 3D. Opisano poszczególne metody i narzędzia niezbędne do realizacji wydruków 3D. Omówiono także materiały, które są wykorzystywane w technologii druku 3D. Ponadto omówiono budowę drukarek, na których zostały przygotowane próbki do badań opisanych w tejże pracy. Przedstawiono wady i zalety korzystania z poszczególnych slicerów do druku 3D. Zaprezentowano otrzymane wyniki pomiarowe próbek wykonanych z polilaktydu (PLA). Pracę podsumowano wnioskami końcowymi.
EN
PLA/nanofibrillar cellulose (NFC) composite films were produced by solution casting. Before use, the cellulose fibers were modified with various types of surface active agents – cationic, anionic and non-ionic surfactants. The structure and morphology of samples of the cellulose fillers and composite films with polymer were analyzed by means of scanning electron microscopy and PXRD diffraction. Thermal parameters of the composite films were characterized by differential scanning calorimetry and thermogravimetric analysis. The tensile strength and elongation at break of the films were evaluated in mechanical tests. The ability to disintegrate of all PLA/NFC composites under composting conditions was also determined and compared.
EN
Purpose: The FDM (Fused Deposition Modelling) additive manufacturing process is characterised by a large number of process variables that determine the mechanical properties and quality of the manufactured parts. When printing layer by layer, the filaments constituting the layer are welded on the one hand between them in the same layer and on the other hand between the superimposed layers, this welding develops on the contact surfaces (raster width) along the deposited filaments. The quality of this welding determines the resistance to crack propagation between filaments and between layers. This article aims to study the effect of the width of the raster on the resistance to crack propagation in a structure obtained by FDM. Design/methodology/approach: We have developed an experimental approach from CT specimens to determine the tensile strength of polylactic acid (PLA) polymers, considering the J-Integral method. And given the complexity of the problem, three cases of raster width (l=0.42 mm, l=0.56 mm and l=0.68 mm) have been treated. Findings: According to the results obtained (J, ∆a), the resistance to crack propagation in the parts printed by FDM seems to be better when the width of the filament is small. Indeed, the energy necessary to break the specimen is relatively greater than in the case of a larger width. This finding was confirmed by comparing the values of J for a given advancement of the crack for the three cases studied. Research limitations/implications: In order to present an exhaustive study, we focused on the effect of raster widths (including 0.42 mm, 0.56 mm to 0.68 mm) on the crack propagation of printed PLA. This study is in progress for other printing parameters. To highlight the cracking mechanisms, microscopic observations will be developed in greater depth at the SEM. Practical implications: Our analysis can be used as decision support in the design of FDM parts. In effect, we can choose the raster width that would provide the resistance to crack propagation desired for a functional part. Originality/value: In this article, we analysed the damage mechanism of CT specimens printed by FDM. This subject represents a new direction for many lines of research. For our study, we used the J-Integral theoretical approach to study the fracture behaviour of these parts by determining the resistance curves (J-∆a).
EN
Chosen flexural and hygroscopic properties of waste wood dust - polylactic acid biocomposite for 3D printing. The study shows chosen flexural and hygroscopic properties of PLA-waste wood dust biocomposite intended for use in 3D printing. Materials were mixed in 3 variants, differentiated by weight content of waste wood dust – 0%, 10%, 20% and 30% and extruded in a two-stage process using an extruder of original design. Variant without waste wood dusts was prepared as well. That filaments were then used to create samples using a 3D printer. For the printed samples chosen properties were tested i.e. MOE, MOR, water absorption and thickness swelling. It was found that waste wood dust does not significantly affect MOR and MOE. It was shown that it’s content negatively impacts the water absorption and thickness swelling. It was demonstrated that the tested material can successfully be used in 3D printing.
PL
Wybrane właściwości higroskopijne oraz mechaniczne przy rozciąganiu biokompozytu odpadowe pyły drzewne – polilaktyd przeznaczonego do druku 3D. Opracowanie przedstawia wybrane właściwości biokompozytu odpadowe pyły drzewne – polilaktyd przeznaczonego do druku 3D. Materiały zostały zmieszane w 3 wariantach, zróżnicowanych pod względem wagowego udziału odpadowych pyłów drzewnych – 0%, 10%, 20% i 30%. Następnie zostały one wyekstrudowane w dwuetapowym procesie przy pomocy autorskiego ekstrudera. Tak przygotowany filament został wykorzystany do wytworzenia próbek przy pomocy drukarki 3D. Dla wydrukowanych próbek zbadano MOE, MOR, nasiąkliwość oraz spęcznienie na grubość. Stwierdzono, że zawartość odpadowych pyłów drzewnych nie wpływa w istotny sposób na MOE i MOR. Wykazano negatywny wpływ odpadowych pyłów drzewnych na nasiąkliwość i spęcznienie na grubość badanego materiału. Stwierdzono, że badany kompozyt może być skutecznie wykorzystywany w druku 3D.
EN
Fused deposition modeling (FDM) is a commonly used additive manufacturing (AM) technique that creates prototypes and parts with intricate geometrical designs. It is gaining popularity since it enhances products by removing the need for expensive equipment. The printed item's mechanical properties are affected by the type of materials used, the printing process, and the printing parameters. The 3-D model of the polylactic acid (PLA) filament generated specimens was created using the Fused Deposition Modeling procedure and developed using Solid Works. This study investigates the effect of printing parameters on the mechanical and physical properties of samples printed using a Fused Deposition Modeling machine (Creality Ender-5 Pro). Six parameters are used: infill pattern, density, overlap percentage, layer thickness, shell thickness, and top/bottom layer number. Five levels were chosen for each FDM parameter. The results illustrated how printing parameters affected the mechanical and physical properties of samples, which were proven by ultimate tensile stress, surface roughness, and percentage of tensile average deviation. A comparison between the predicted results and the measured results was presented, and the maximum percentage error of the model, which fit the data well, was 0.54%, 0.3%, and 1.36% for ultimate tensile strength (UTS), surface roughness (Ra), and Tensile average deviation percentage respectively.
EN
The study addresses the growing need for personalized medicine and cost-effective manufacturing by investigating additive manufacturing (AM). It employs the Design of Experiments (DOE) to explore how fused filament fabrication (FFF) parameters affect porosity and mechanical properties of medical-grade polylactide (PLA) samples.
15
Content available Biodegradable scaffolds for bone defect treatment
EN
Additive techniques in dog orthopedics has recently emerged as a valuable approach in fabricating individualized implants for receiver-specific needs. The scaffolds made by 3D printing are used to replaces bones damaged by injuries sustained in accidents, tumour resections and defects resulting from disease e.g. osteoporosis. In this way can promote the growth and reconstruction of bone defects structure. These implants should have the right properties to ensure the right conditions for bone fusion. It is also important to determine the time of degradation, which is associated with a significant loss of mechanical properties.
EN
The methodology and measurement results of the machine part produced directly from the 3D-CAD numerical model are presented. Representative additive techniques based on polymer processing were used. The accuracy of replication of CAD numerical models was assessed in terms of both external surface analysis and part volume.
PL
Przedstawiono metodykę oraz wyniki pomiarów części maszyny wytworzonej bezpośrednio z modelu numerycznego 3D-CAD. Zastosowano reprezentatywne techniki addytywne bazujące na przetwarzaniu polimerów. Dokonano oceny dokładności replikacji modeli numerycznych CAD zarówno w ujęciu analizy powierzchni zewnętrznych, jak i objętości części.
PL
Celem pracy jest poznanie możliwości i uwarunkowań stosowania modeli wykonanych w technologii druku 3D do badań dynamicznych. Zaprezentowano metodę i wyniki badań określających parametry fizykomechaniczne polimeru PLA-IMPACT drukowanego z różnymi kątami rastrowania. Badania wykazały, że wartość modułu sprężystości polimeru nie zależy od kąta rastrowania, natomiast na granicę plastyczności ma wpływ kierunek laminacji, co wpływa w istotny sposób na realizację modeli obiektów do badań dynamicznych.
EN
The aim of the work is to identify the possibilities and conditions for the use of models made in 3D printing technology for dynamic experiments. The methodology and results of tests determining the physical and mechanical parameters of the PLA-IMPACT polymer printed with different screening angles are presented. The research showed that the value of the polymer modulus of elasticity does not depend on the rastering angle, while the yield point depends on the direction of lamination, which is of key importance in the implementation of models of objects for dynamic tests.
EN
Purpose: In the Fused Filament Fabrication (FFF/FDM) technology, the multi-material manufacturing additive method is achieved by a single nozzle or multiple nozzles working simultaneously with different materials. However, the adhesion between different materials at the boundary interface in FDM multi-material printing is a limiting factor. These studies are concerned with improving and study the adhesion between two polymers. Design/methodology/approach: Due to the numerous applications and possibilities of 3D printed objects, combining different materials has become a subject of interest. PLA is an alternative to the use of petrochemical-based polymers. Thermoplastic Polyurethane is a flexible material that can achieve different characteristics when combined with a rigid filament, such as PLA. To improve the adhesion between PLA and TPU in multi-material FFF/FDM, we propose the comparison of different processes: post-processing with acetone immersion, surface activation during printing with Acetone, surface activation during printing with tetrahydrofuran, post-processing annealing, and connection of printed parts with tetrahydrofuran. Findings: Modifying the 3D printing process improved the quality of the adhesive bond between the two different polymers. Activation of the surface with THF is the treatment method recommended by the authors due to the low impact on the deformation/degradation of the object. Research limitations/implications: In the study, adhesion was considered in relation to the circular pattern of surface development. Further analysis should include other surface development patterns and changes in printing parameters, e.g. process temperatures and layer application speed. Practical implications: 3D printing with multi-materials, such as PLA biopolymer and thermoplastic polyurethane, allows for the creation of flexible connections. The strengthening of the biopolymer broadens the possibilities of using polylactide. Examples of applications include: automotive (elements, where flexible TPU absorbs vibrations and protects PLA from cracking), medicine (prostheses with flexible elements ensuring mobility in the joints). Originality/value: Multi-material printing is a new trend in 3D printing research, and this research is aimed at promoting the use and expanding the possibilities of using PLA biopolymer.
PL
Celem badań było wytworzenie za pomocą wytłaczarki 3Devo trzech różnych filamentów na bazie tworzywa PLA: bez domieszek, z miedzią oraz z grafitem. Dla wytłoczonych filamentów sprawdzono takie parametry, jak chropowatość, uzyskaną średnicę oraz siłę zerwania. Powstała struktura kompozytowa przeznaczona jest do druku 3D w technologii FDM (fused deposition modeling), z wykorzystaniem szybkiego prototypowania.
EN
The aim of the research was to produce three different PLA-based filaments using the 3Devo extruder: without admixtures, with copper and with graphite. For these filaments, parameters such as roughness, obtained diameter and breaking force were checked. The resulting composite structure is intended for 3D printing in FDM (fused deposition modeling) technology, using rapid prototyping.
20
Content available Wood plastic composites as a substitution for HDF
EN
Wood plastic composites as a substitution for HDF. As part of the research, industrial HDF boards were used and WPC composites were produced, differentiated in terms of matrix (PLA and HDPE) and filler content (40%, 50% and 60%). The density and density profile was measured to compare HDF and WPC structure. In addition, the manufactured boards were tested for strength (MOR, MOE), screw holding, thickness swelling and water absorption after immersion in water for 2 and 24 hours. WPC were characterized by a higher density than HDF boards and a uniform density profile. In addition, WPC composites were characterized by lower MOR and MOE values than HDF boards. Compared to HDF boards, WPC composites were characterized by higher values of screw holding and better resistance to moisture.
PL
Kompozyty WPC jako substytut płyt HDF. W ramach badań wykorzystano przemysłowe płyty HDF oraz wytworzono kompozyty WPC zróżnicowane pod kątem matrycy (PLA i HDPE) oraz udziału napełniacza (40%, 50% i 60%). Oznaczono gęstość i profil gęstości w celu porównania struktury HDF i WPC. Ponadto wytworzone płyty zostały przetestowane pod kątem wytrzymałości (MOR, MOE), utrzymania wkrętów, spęcznienia na grubość oraz nasiąkliwości po moczeniu w wodzie przez 2 i 24 godziny. WPC charakteryzowały się wyższa gęstością niż płyty HDF oraz jednorodnym profilem gęstości. Ponadto kompozyty WPC charakteryzowały się niższymi wartościami MOR i MOE niż płyty HDF. W porównaniu do płyt HDF kompozyty WPC charakteryzowały się wyższymi wartościami zdolności utrzymania wkrętów oraz lepszą odpornością na działanie wilgoci.
first rewind previous Strona / 7 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.