A study of tensile and bending properties of 3D-printed biocompatible materials used in dental appliances

AbstractIn the last years, a large number of new biocompatible materials for 3D printers have emerged. Due to their recent appearance and rapid growth, there is little information about their mechanical properties. The design and manufacturing of oral appliances made with 3D printing technologies require knowledge of the mechanical properties of the biocompatible material used to achieve optimal performance for each application. This paper focuses on analysing the mechanical behaviour of a wide range of biocompatible materials using different additive manufacturing technologies. To this end, tensile and bending tests on different types of recent biocompatible materials used with 3D printers were conducted to evaluate the influence of the material, 3D printing technology, and printing orientation on the fragile/ductile behaviour of the manufactured devices. A test bench was used to perform tensile tests according to ASTM D638 and bending tests according to ISO 178. The specimens were manufactured with nine different materials and five manufacturing technologies. Furthermore, specimens were created with different printing technologies, biocompatible materials, and printing orientations. The maximum allowable stress, rupture stress, flexural modulus, and deformation in each of the tested specimens were recorded. Results suggest that specimens manufactured with Stereolithography (SLA) and milling (polymethyl methacrylate PMMA) achieved high maximum allowable and rupture stress values. It was also observed that Polyjet printing and Selective Laser Sintering technologies led to load–displacement curves with low maximum stress and high deformation values. Specimens manufactured with Digital Light Processing technology showed intermediate and homogeneous performance. Finally, it was observed that the printing direction significantly influences the mechanical properties of the manufactured specimens in some cases.

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Thermoplastics and Photopolymer Desktop 3D Printing System Selection Criteria Based on Technical Specifications and Performances for Instructional Applications

Technologies ◽

10.3390/technologies9040091 ◽

2021 ◽

Vol 9 (4) ◽

pp. 91

Author(s):

Bruce W. Jo ◽

Christina Soyoung Song

Keyword(s):

3D Printing ◽

Selection Criteria ◽

Material Selection ◽

Basic Knowledge ◽

Comprehensive Overview ◽

Wide Range ◽

3D Printers ◽

Technical Specifications ◽

Technical Features ◽

Manufacturing Technologies

With the advancement of additive manufacturing technologies in their material processing methodologies and variety of material selection, 3D printers are widely used in both academics and industries for various applications. It is no longer rare to have a portable and small desktop 3D printer and manufacture your own designs in a few hours. Desktop 3D printers vary in their functions, prices, materials used, and applications. Among many desktop 3D printers with various features, it is often challenging to select the best one for target applications and usages. In this paper, commercially available and carefully selected thermoplastic and photopolymer desktop 3D printers are introduced, and some representative models’ specifications and performances are compared with each other for user selection with respect to instructional applications. This paper aims to provide beginner-level or advanced-level end-users of desktop 3D printers with basic knowledge, selection criteria, a comprehensive overview of 3D printing technologies, and their technical features, helping them to evaluate and select the right 3D printers for a wide range of applications.

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An Overview on the Rheology, Mechanical Properties, Durability, 3D Printing, and Microstructural Performance of Nanomaterials in Cementitious Composites

Materials ◽

10.3390/ma14112950 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2950

Author(s):

Hongwei Song ◽

Xinle Li

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Three Dimensional ◽

Cementitious Materials ◽

Research Area ◽

Cementitious Composites ◽

Split Tensile Strength ◽

Contour Crafting ◽

Wide Range ◽

Active Research

The most active research area is nanotechnology in cementitious composites, which has a wide range of applications and has achieved popularity over the last three decades. Nanoparticles (NPs) have emerged as possible materials to be used in the field of civil engineering. Previous research has concentrated on evaluating the effect of different NPs in cementitious materials to alter material characteristics. In order to provide a broad understanding of how nanomaterials (NMs) can be used, this paper critically evaluates previous research on the influence of rheology, mechanical properties, durability, 3D printing, and microstructural performance on cementitious materials. The flow properties of fresh cementitious composites can be measured using rheology and slump. Mechanical properties such as compressive, flexural, and split tensile strength reveal hardened properties. The necessary tests for determining a NM’s durability in concrete are shrinkage, pore structure and porosity, and permeability. The advent of modern 3D printing technologies is suitable for structural printing, such as contour crafting and binder jetting. Three-dimensional (3D) printing has opened up new avenues for the building and construction industry to become more digital. Regardless of the material science, a range of problems must be tackled, including developing smart cementitious composites suitable for 3D structural printing. According to the scanning electron microscopy results, the addition of NMs to cementitious materials results in a denser and improved microstructure with more hydration products. This paper provides valuable information and details about the rheology, mechanical properties, durability, 3D printing, and microstructural performance of cementitious materials with NMs and encourages further research.

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Analysis of the Impact on the Mechanical Properties of Modification of Oligohydroxyethers in Organic Solvent Solution with Rubbers

Polymers ◽

10.3390/polym13040519 ◽

2021 ◽

Vol 13 (4) ◽

pp. 519

Author(s):

Vitalii Bezgin ◽

Agata Dudek ◽

Adam Gnatowski

Keyword(s):

Mechanical Properties ◽

Scientific Paper ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Molecular Weights ◽

Wide Range ◽

Strength Tests ◽

Materials Used ◽

Styrene Butadiene ◽

The Impact

This paper proposes and presents the chemical modification of linear hydroxyethers (LHE) with different molecular weights (380, 640, and 1830 g/mol) with the addition of three types of rubbers (polysulfide rubber (PSR), polychloroprene rubber (PCR), and styrene-butadiene rubber (SBR)). The main purpose of choosing this type of modification and the materials used was the possibility to use it in industrial settings. The modification process was conducted for a very wide range of modifier additions (rubber) per 100 g LHE. The materials obtained in the study were subjected to strength tests in order to determine the effect of the modification on functional properties. Mechanical properties of the modified materials were improved after the application of the modifier (rubber) to polyhydroxyether (up to certain modifier content). The most favorable changes in the tested materials were registered in the modification of LHE-1830 with PSR. In the case of LHE-380 and LHE-640 modified in cyclohexanol (CH) and chloroform (CF) solutions, an increase in the values of the tested properties was also obtained, but to a lesser extent than for LHE-1830. The largest changes were registered for LHE-1830 with PSR in CH solution: from 12.1 to 15.3 MPa for compressive strength tests, from 0.8 to 1.5 MPa for tensile testing, from 0.8 to 14.7 MPa for shear strength, and from 1% to 6.5% for the maximum elongation. The analysis of the available literature showed that the modification proposed by the authors has not yet been presented in any previous scientific paper.

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3D Printing Part 2 - A Literature Review Of 3D Printing Materials in Dentistry

10.20944/preprints202105.0316.v1 ◽

2021 ◽

Author(s):

Adam Brian Nulty

Keyword(s):

3D Printing ◽

High Performance ◽

Cost Effective ◽

Future Evolution ◽

Cost Effective Treatment ◽

Wide Range ◽

Milling Machines ◽

Cad Cam ◽

Subtractive Manufacturing ◽

3D Printers

Introduction: The current generation of 3D printers are lighter, cheaper, and smaller, making them more accessible to the chairside digital dentist than ever before. 3D printers in general in the industrial and chairside setting can work with various types of materials including, metals, ceramics, and polymers. Evidence presented in many studies show that an ideal material used for dental restorations is characterised by several properties related to durability, cost-effectiveness, and high performance. This review is the second part in a 3D Printing series that looks at the literature on material science and applications for these materials in 3D printing as well as a discussion on the potential further development and future evolution in 3D printing materials. Conclusions: Current materials in 3D printing provide a wide range of possibilities for providing more predictable workflows as well as improving efficiency through less wasteful additive manufacturing in CAD/CAM procedures. Incorporating a 3D printer and a digital workflow into a dental practice is challenging but the wide range of manufacturing options and materials available mean that the dentist should be well prepared to treat patients with a more predictable and cost effective treatment pathway. As 3D printing continues to become a commonplace addition to chair side dental clinics, the evolution of these materials, in particular reinforced PMMA, resin incorporating zirconia and glass reinforced polymers offer increased speed and improved aesthetics that will likely replace subtractive manufacturing milling machines for most procedures.

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3D printing of biofiber-reinforced composites and their mechanical properties: a review

Rapid Prototyping Journal ◽

10.1108/rpj-08-2019-0214 ◽

2020 ◽

Vol 26 (6) ◽

pp. 1113-1129

Author(s):

Lai Jiang ◽

Xiaobo Peng ◽

Daniel Walczyk

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Reinforced Composites ◽

Research Directions ◽

Content Type ◽

Reinforced Composite ◽

3D Printed ◽

Materials Used ◽

Printing Processes ◽

Pure Resin

Purpose This paper aims to summarize the up-to-date research performed on combinations of various biofibers and resin systems used in different three-dimensional (3D) printing technologies, including powder-based, material extrusion, solid-sheet and liquid-based systems. Detailed information about each process, including materials used and process design, are described, with the resultant products’ mechanical properties compared with those of 3D-printed parts produced from pure resin or different material combinations. In most processes introduced in this paper, biofibers are beneficial in improving the mechanical properties of 3D-printed parts and the biodegradability of the parts made using these green materials is also greatly improved. However, research on 3D printing of biofiber-reinforced composites is still far from complete, and there are still many further studies and research areas that could be explored in the future. Design/methodology/approach The paper starts with an overview of the current scenario of the composite manufacturing industry and then the problems of advanced composite materials are pointed out, followed by an introduction of biocomposites. The main body of the paper covers literature reviews of recently emerged 3D printing technologies that were applied to biofiber-reinforced composite materials. This part is classified into subsections based on the form of the starting materials used in the 3D printing process. A comprehensive conclusion is drawn at the end of the paper summarizing the findings by the authors. Findings Most of the biofiber-reinforced 3D-printed products exhibited improved mechanical properties than products printed using pure resin, indicating that biofibers are good replacements for synthetic ones. However, synthetic fibers are far from being completely replaced by biofibers due to several of their disadvantages including higher moisture absorbance, lower thermal stability and mechanical properties. Many studies are being performed to solve these problems, yet there are still some 3D printing technologies in which research concerning biofiber-reinforced composite parts is quite limited. This paper unveils potential research directions that would further develop 3D printing in a sustainable manner. Originality/value This paper is a summary of attempts to use biofibers as reinforcements together with different resin systems as the starting material for 3D printing processes, and most of the currently available 3D printing techniques are included herein. All of these attempts are solutions to some principal problems with current 3D printing processes such as the limit in the variety of materials and the poor mechanical performance of 3D printed parts. Various types of biofibers are involved in these studies. This paper unveils potential research directions that would further widen the use of biofibers in 3D printing in a sustainable manner.

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Effects of Hydrophobic Barrier Films on the Mechanical Properties of Fiber Reinforced Composites Immersed in Water

Volume 1: Advances in Aerospace Technology; Energy Water Nexus; Globalization of Engineering; Posters ◽

10.1115/imece2011-62752 ◽

2011 ◽

Cited By ~ 1

Author(s):

E. Kececi ◽

R. Asmatulu

Keyword(s):

Mechanical Properties ◽

Moisture Absorption ◽

Uv Light ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Bending Tests ◽

Barrier Films ◽

Hydrophobic Barrier ◽

Wide Range

Fiber reinforced composites are subjected to a wide range of mechanical loads and environmental conditions, such as wind, high/low temperature, moisture, UV light and aggressive solvents. Compared to other structural materials, polymers can absorb more moisture and UV light from outside environment and lose their material properties (e.g., mechanical, electrical, surface and thermal) and thus the service life. In this study, hydrophobic barrier films including polyvinylfluoride (PVF) and polyether ether ketone (PEEK) were applied on the carbon, Kevlar, and glass fiber reinforced epoxy resin composites (laminate and sandwich structures), and then the effects of moisture absorption on those films were investigated in detail. The coupons were immersed in water for a number of days in order to determine the changes in mechanical properties of the composites. Three point bending tests were applied to the laminate composites, while four point bending tests were conducted on the Nomex sandwich structured composites. We found that moisture absorption could be eliminated by using these hydrophobic films. We found that PEEK film could be an alternative barrier film for the aircraft industry.

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Possible Applications of Additive Manufacturing Technologies in Shipbuilding: A Review

Machines ◽

10.3390/machines8040084 ◽

2020 ◽

Vol 8 (4) ◽

pp. 84

Author(s):

Marcin Ziółkowski ◽

Tomasz Dyl

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

3D Printing ◽

Weight Reduction ◽

Maritime Industry ◽

High Quality ◽

Printing Technology ◽

3D Printing Technology ◽

Manufacturing Technologies ◽

Very High

3D printing conquers new branches of production due to becoming a more reliable and professional method of manufacturing. The benefits of additive manufacturing such as part optimization, weight reduction, and ease of prototyping were factors accelerating the popularity of 3D printing. Additive manufacturing has found its niches, inter alia, in automotive, aerospace and dentistry. Although further research in those branches is still required, in some specific applications, additive manufacturing (AM) can be beneficial. It has been proven that additively manufactured parts have the potential to out perform the conventionally manufactured parts due to their mechanical properties; however, they must be designed for specific 3D printing technology, taking into account its limitations. The maritime industry has a long-standing tradition and is based on old, reliable techniques; therefore it implements new solutions very carefully. Besides, shipbuilding has to face very high classification requirements that force the use of technologies that guarantee repeatability and high quality. This paper provides information about current R&D works in the field of implementing AM in shipbuilding, possible benefits, opportunities and threats of implementation.

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Additive technologies in military affairs

Russian Military Medical Academy Reports ◽

10.17816/rmmar77796 ◽

2021 ◽

Vol 40 (2) ◽

pp. 5-12

Author(s):

Stepan A. Peleshok ◽

Aleksandr Ya. Fisun ◽

Andrey V. Morozov ◽

Sergey V. Kalinin ◽

Marina I. Eliseeva

Keyword(s):

3D Printing ◽

Round Table ◽

Additive Technologies ◽

Educational Process ◽

Nuclear Industry ◽

Educational Institutions ◽

Industrial Complex ◽

Wide Range ◽

3D Printers ◽

The Creation

In order to determine the features and main ways of using additive technologies within the framework of the scientific and business program of the International Military-Technical Forum Army-2020, a round table was held. In recent years, additive technologies have made a significant leap forward thanks to the improvement of electronic computing technology and software (software), the creation of a wide range of 3D printers that print using various modern methods and materials. The following industries are leading in the development of 3D printing as consumers: aircraft construction (33%), nuclear industry (30%), military-industrial complex (13%), as well as medicine (11%), education, etc. The summary contains part of the speeches of the speakers of the scientific event on the use of additive technologies in education and medicine. To achieve Russias position as one of the leaders in the global technology market, a network of educational institutions is developing and the provision of educational institutions with 3D printers. The countrys universities and, in particular, Bauman Moscow State Technical University began to develop professional competencies among graduates in the field of additive technologies, materials and equipment. Other universities use reverse engineering for research and development, the launch of new production. In medicine, models of complex elements of the human skeleton are created, in particular, individual bones and various projections of the skull, bones of the spine, hand and foot, as well as some models of organs from hard and semi-soft plastics to improve the educational process. The capabilities of 3D printing of mock-ups of organ pathologies are used for preoperative planning and rehearsal of an operation in thoracic and cardiovascular surgery, as well as for training students and doctors, modeling hemodynamics and testing medical devices. Alternative materials and methods for making splints and splints for fixing injuries and diseases of the upper limb are considered. To create ceramic products in dentistry, instead of injection molding and pressing, the technology of Lithography-based Ceramics Manufacturing printing with a suspension on foreign equipment was proposed. Three-dimensional printing has partially filled the need for personal protective equipment against the new coronavirus infection, in particular through the creation of reusable masks, various adapters, holders of face masks, linings on door handles, etc. The participants of the round table agreed that the results of scientific and innovative activities in the field of additive technologies should be tested, implemented and used in the educational process, practical activities, including military medicine (bibl.: 6 refs).

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Determination of mechanical properties of materials used for 3D printing

MANUFACTURING TECHNOLOGY ◽

10.21062/mft.2020.029 ◽

2020 ◽

Vol 20 (2) ◽

pp. 190-194

Author(s):

Josef Sedlak ◽

Josef Chladil ◽

Martin Cerny ◽

Ales Polzer ◽

Matus Varhanik ◽

...

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Mechanical Properties Of Materials ◽

Properties Of Materials ◽

Materials Used

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The Change of the 3D Printing Product Mechanical Properties in the Function of Different Post-Treatment

Materials Science Forum ◽

10.4028/www.scientific.net/msf.659.183 ◽

2010 ◽

Vol 659 ◽

pp. 183-189 ◽

Cited By ~ 1

Author(s):

Norbert Krisztián Kovács ◽

József Gábor Kovács

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Product Design ◽

Treatment Method ◽

Post Treatment ◽

Cad Model ◽

Layer By Layer ◽

Design And Manufacturing ◽

Subtractive Manufacturing ◽

Manufacturing Technologies

Rapid prototyping (RP) has changed the method of product design and manufacturing. With the help of RP technologies a physical model can be created within couple of hours from any complex CAD model. RP technologies in contrast with conventional subtractive manufacturing technologies produce the end product by adding material layer-by-layer. 3D printing is one of the most widespread technologies in the industry. Because of the porous structure and bad mechanical properties of the models further post treatment is needed. Post treatment always means infiltration of the models, in case of gypsum and cellulose epoxy resin is mostly used. In our work the effect of post treatment method was examined on the mechanical properties of the pieces. The investigated pieces were prepared with four different setting of a printer.

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