Research into the mechanical properties, sintering mechanism and microstructure evolution of Al2O3-ZrO2 composites fabricated by a stereolithography-based 3D printing method

The results of the studies of the effect of excipients of mineral and organic origin on the mechanical properties of polyether sulfone based on 4,4'-dihydroxydiphenyl and 4,4'-dichlordiphenylsulfone are adduced. It has been shown that the introduction of hard fillers is accompanied by the increased modulus and reduced ductility of the polymer matrix, the intensity of these effects depends on the concentration, shape and particle size additives. It was revealed that the composites with talc and discrete carbon fibers were characterized by higher mechanical properties. Their test as materials for FDM 3D printing method shows the highest suitability composites with talc for this technology.

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Research and Implementation of Axial 3D Printing Method for PLA Pipes

Applied Sciences ◽

10.3390/app10134680 ◽

2020 ◽

Vol 10 (13) ◽

pp. 4680

Author(s):

Haiguang Zhang ◽

Wenguang Zhong ◽

Qingxi Hu ◽

Mohamed Aburaia ◽

Joamin Gonzalez-Gutierrez ◽

...

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

3D Printing ◽

Layer By Layer ◽

Standard Material ◽

Material Extrusion ◽

G Code ◽

Realization Process ◽

Actual Stress ◽

Printing Method

Additive manufacturing has been applied in many fields, but its layer-by-layer fabrication process leads to a weak inter-layer bond strength of printed parts, so it cannot meet the higher requirements for mechanical properties of the industry. At present, many researchers are studying the printing path planning method to improve the mechanical properties of printed parts. This paper proposes a method to plan the printing path according to the actual stress of pipe parts, and introduces the realization process of an algorithm in detail, and obtains the printing control G-code. Additionally, a 5-axis material extrusion platform was built to realize the printing of polylactic acid pipes with plane and space skeleton curves, respectively, which verified the feasibility and applicability of the method and the correctness of the planning path with standard material extrusion filaments. Finally, the tensile and bending experiments prove that axial printing enhances the mechanical properties of pipe parts.

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3D Printing of Aramid Nanofiber Composites by Stereolithography

10.26434/chemrxiv-2021-5pj1d ◽

2021 ◽

Author(s):

Sachini Perera ◽

Alejandra Durand-Silva ◽

Ashele Remy ◽

Shashini Diwakara ◽

Ronald Smaldone

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Exchange Process ◽

Polymeric Materials ◽

Solvent Exchange ◽

High Quality ◽

Filler Dispersion ◽

Printing Method ◽

Quality Surface ◽

High Quality Surface

Vat photopolymerization is a versatile 3D printing method that produces parts using polymeric materials with uniform mechanical properties, high quality surface finish and high-resolution features. However, it is challenging to make composite materials with vat photopolymerization mainly due to the imperfect filler dispersion in the photo resin. Herein, we describe a methodology to incorporate aramid nanofibers (ANFs) into a 3D printable photoresin as a dispersion, followed by a solvent exchange process that limits anisotropic shrinkage and cracking of the printed polymer. By incorporating 0.60 wt.% of ANFs, both the tensile strength and toughness increased by 264 % and 219 % respectively, while the Young’s modulus had a 406 % increase compared to the control photoresin.

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The Study of Physico-Mechanical Properties of Polylactide Composites with Different Level of Infill Produced by the FDM Method

Polymers ◽

10.3390/polym12123056 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3056

Author(s):

Anna Gaweł ◽

Stanisław Kuciel

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Mechanical Strength ◽

Elevated Temperatures ◽

Mechanical Energy ◽

Hydrolytic Degradation ◽

Physiological Saline ◽

Light Weight ◽

Strength Variability ◽

Printing Method

The aim of this study was to evaluate the changes in physical-mechanical properties of the samples manufactured by 3D printing technology with the addition of varying degrees of polylactide (PLA) infill (50, 70, 85 and 100%). Half of the samples were soaked in physiological saline. The material used for the study was neat PLA, which was examined in terms of hydrolytic degradation, crystallization, mechanical strength, variability of properties at elevated temperatures, and dissipation of mechanical energy depending on the performed treatment. A significant impact of the amount of infill on changeable mechanical properties, such as hydrolytic degradation and crystallization was observed. The FDM printing method allows for waste–free production of light weight unit products with constant specyfic strength.

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Research on the Influence of the Orientation of Deposited Material on the Mechanical Properties of Samples Made from ABS M30 Material Using the 3D Printing Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.809-810.429 ◽

2015 ◽

Vol 809-810 ◽

pp. 429-434

Author(s):

Răzvan Păcurar ◽

Ancuţa Păcurar ◽

Adrian Radu Sever

Keyword(s):

Mechanical Properties ◽

Finite Element Method ◽

3D Printing ◽

Mechanical Strength ◽

3D Printer ◽

The Finite Element Method ◽

Building Orientation ◽

3D Printers ◽

Polymer Deposition ◽

Printing Method

The majority of commercially available 3D printers utilize an additive manufacturing (AM) technique known as molten polymer deposition, whereby a solid thermoplastic filament is forced through a computer-driven extrusion nozzle. Even if it sounds simple at a first look, there are a series of factors that significantly influence the mechanical strength of parts manufactured by using the 3D printing method. The present work tries to investigate by using the finite element method and experimental research how the building orientation is influencing the mechanical strength of samples made from ABS M30 material using a Desktop 3D Printer machine that has been originally designed and produced at the Technical University of Cluj-Napoca (TUC-N).

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Mechanical Properties of Dental Alloys According to Manufacturing Process

Materials ◽

10.3390/ma14123367 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3367

Author(s):

Ji-Min Yu ◽

Seen-Young Kang ◽

Jun-Seok Lee ◽

Ho-Sang Jeong ◽

Seung-Youl Lee

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Yield Strength ◽

Modulus Of Elasticity ◽

Three Dimensional ◽

Dimensional Structure ◽

Dental Alloys ◽

Cad Cam ◽

Scheffe Method ◽

Printing Method

The purpose of this study is to investigate the effect of the fabrication method of dental prosthesis on the mechanical properties. Casting was produced using the lost wax casting method, and milling was designed using a CAD/CAM program. The 3D printing method used the SLS technique to create a three-dimensional structure by sintering metal powder with a laser. When making the specimen, the specimen was oriented at 0, 30, 60, and 90 degrees. All test specimens complied with the requirements of the international standard ISO 22674 for dental alloys. Tensile strength was measured for yield strength, modulus of elasticity and elongation by applying a load until fracture of the specimen at a crosshead speed of 1.5 ± 0.5 mm/min (n = 6, modulus of elasticity n = 3). After the tensile test, the cross section of the fractured specimen was observed with a scanning electron microscope, and the statistics of the data were analyzed with a statistical program SPSS (IBM Corp. Released 2020. IBM SPSS Statistics for Windows, Version 27.0. Armonk, NY, USA: IBM Corp.) and using Anova and multiple comparison post-tests (scheffe method). The yield strength was the highest at 1042 MPa at an angle of 0 degrees in the specimen produced by 3D printing method, and the elongation was the highest at 14% at an angle of 90 degrees in the specimen produced by 3D printing method. The modulus of elasticity was the highest at 235 GPa in the milled specimen. In particular, the 3D printing group showed a difference in yield strength and elongation according to the build direction. The introduction of various advanced technologies and digital equipment is expected to bring high prospects for the growth of the dental market.

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Effect of High-Pressure Hot Airflow On Interlayer Adhesion Strength of 3D Printed Parts

10.21203/rs.3.rs-1151495/v1 ◽

2021 ◽

Author(s):

Huangxiang Xu ◽

Jianhua Xiao ◽

Xiaojie Zhang ◽

Xiaobo Liu

Keyword(s):

Mechanical Properties ◽

High Pressure ◽

Surface Layer ◽

3D Printing ◽

Adhesion Strength ◽

Gas Flow ◽

Dimensional Accuracy ◽

Lubrication Layer ◽

3D Printed ◽

Printing Method

Abstract The characteristics of FDM 3D printed parts depend largely on the process used to make them. This paper demonstrates the design of an FDM 3D printing gas-assisted molding printing head, which is used to eliminate the effect of swelling away from the mold and improve the dimensional accuracy. Meanwhile, the high-pressure hot airflow instantly heats and pressurizes the printing surface layer to enhance the interlayer adhesion strength and its mechanical properties. A stable gas lubrication layer can be formed on the inner wall of gas-assisted nozzle to smoothly deposit filaments when the gas flow (Qgas) is set to 1.75 L/min and the gas pressure (Pgas) is set to 0.4 MPa. The interlayer adhesion strength of the printed parts is enhanced by more than 50% compared with that without gas assistance, and the volumetric shrinkage rate of the optimal group is only 0.13%. The proposed printing method can significantly improve the performance of thermoplastic parts and provide new capabilities for biomedical printing, automotive, aerospace and functional device printing in the future.

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Design of thermoformable three dimensional-printed PLA cast for fractured wrist

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1217/1/012002 ◽

2022 ◽

Vol 1217 (1) ◽

pp. 012002

Author(s):

N P Sorimpuk ◽

W H Choong ◽

B L Chua

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Three Dimensional ◽

Maximum Load ◽

Production Method ◽

Patient Specific ◽

Element Analysis ◽

Plaster Of Paris ◽

3D Printed ◽

Printing Method

Abstract Patient specific plastic cast for broken limbs has been developed recently in pharmaceutical field through three-dimensional (3D) printing method. However, the production of a 3D printed cast through normal 3D printing method is time consuming compared to conventional plaster casting. In this study, a design of ventilated structured thermoformable 3D-printed polylactic acid (PLA) cast was produced as an alternative for the 3D printed cast production method. This design was initially printed in a flat shape and then transformed into a cast which can be fitted to the user’s arm by using heat and external force. Finite Element Analysis (FEA) method was used to assess the mechanical properties of the proposed cast. In this analysis, thethermoformable design was exerted with a distributed force of 400 N, which is larger than the loading conditions encountered by human in their daily life. The mechanical properties of the thermoformable PLA cast such as local displacement under a specific load, maximum load, and stress were evaluated. Results were compared with the mechanical properties of Plaster of Paris cast. The results obtained from the FEA indicates that at the same layer thickness, the thermoformable 3D-printed PLA cast is stronger than the Plaster of Paris cast.

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