Recent Advancements in Biomimetic 3D Printing Materials With Enhanced Mechanical Properties

Nature has developed a wide range of functional microstructures with optimized mechanical properties over millions of years of evolution. By learning from nature’s excellent models and principles, biomimicry provides a practicable strategy for designing and fabricating the next smart materials with enhanced properties. Nevertheless, the complicated micro-structural constructions in nature models are beyond the ability of conventional processes, hindering the developments of biomimetic research and its forthputting in engineering systems. Additive manufacturing (AM) or 3D printing processes have revolutionized manufacturing via their ability to manufacture complex micro/mesostructures, increase design freedom, provide mass customization, and waste minimization, as well as rapid prototyping. Here, a review of recent advances in biomimetic 3D printing materials with enhanced mechanical properties is provided. The design and fabrication were inspired by various natural structures, such as balsa wood, honeycomb, nacre, lobster claw, etc., which are presented and discussed. Finally, future challenges and perspectives are given.

Download Full-text

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.

Download Full-text

Fused filament fabrication: A comprehensive review

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705720970629 ◽

2020 ◽

pp. 089270572097062

Author(s):

Sudhir Kumar ◽

Rupinder Singh ◽

TP Singh ◽

Ajay Batish

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Smart Materials ◽

Low Cost ◽

Processing Parameters ◽

View Point ◽

Fused Filament Fabrication ◽

Comprehensive Review ◽

Smart Composites ◽

Complex Design

Fused filament fabrication (FFF) is one of the low cost additive manufacturing (AM) techniques capable of printing complex design (both with commercial and non-commercial feedstock filaments by using different processing parameters). In this paper a comprehensive review has been prepared on FFF operating capabilities from thermoplastics material’s view point. Various thermoplastic materials and composites available commercially and prepared at laboratory scale have been categorized based upon the reported studies performed (for thermal stability, mechanical properties etc.). It was observed that the nano composite based feed stock filament (prepared at lab scale) have edge over the micro-composites from thermo-mechanical properties view point. Further it has been noticed that the 3D printing is in changing phase and moving towards 4D printing of smart composites and designs. But hitherto little has been reported on printing of smart material with FFF platform. Further studies may be focused on printing of smart materials (both micro and nano composites) with FFF, as the low cost 3D printing solution in different engineering applications.

Download Full-text

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.

Download Full-text

Possibilities of Preoperative Medical Models Made by 3D Printing or Additive Manufacturing

Journal of Medical Engineering ◽

10.1155/2016/6191526 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6 ◽

Cited By ~ 20

Author(s):

Mika Salmi

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

3D Modeling ◽

Mechanical Engineering ◽

3D Model ◽

Model Reconstruction ◽

3D Model Reconstruction ◽

Wide Range ◽

Printing Processes ◽

Binder Jetting

Most of the 3D printing applications of preoperative models have been focused on dental and craniomaxillofacial area. The purpose of this paper is to demonstrate the possibilities in other application areas and give examples of the current possibilities. The approach was to communicate with the surgeons with different fields about their needs related preoperative models and try to produce preoperative models that satisfy those needs. Ten different kinds of examples of possibilities were selected to be shown in this paper and aspects related imaging, 3D model reconstruction, 3D modeling, and 3D printing were presented. Examples were heart, ankle, backbone, knee, and pelvis with different processes and materials. Software types required were Osirix, 3Data Expert, and Rhinoceros. Different 3D printing processes were binder jetting and material extrusion. This paper presents a wide range of possibilities related to 3D printing of preoperative models. Surgeons should be aware of the new possibilities and in most cases help from mechanical engineering side is needed.

Download Full-text

Exploring Smart Material Applications for COVID-19 Pandemic Using 4D Printing Technology

Journal of Industrial Integration and Management ◽

10.1142/s2424862220500219 ◽

2020 ◽

Vol 05 (04) ◽

pp. 481-494

Author(s):

Mohd Javaid ◽

Abid Haleem

Keyword(s):

3D Printing ◽

Smart Materials ◽

Smart Material ◽

Layer By Layer ◽

4D Printing ◽

Medical Field ◽

Additional Element ◽

Printing Technology ◽

Innovative Solutions ◽

Printing Processes

Today, in the medical field, innovative technological advancements support healthcare systems and improve patients’ lives. 4D printing is one of the innovative technologies that creates notable innovations in the medical field. For the COVID-19 pandemic, this technology proves to be useful in the manufacturing of smart medical parts, which helps treat infected patients. As compared to 3D printing, 4D printing adds time as an additional element in the manufactured part. 4D printing uses smart materials with the same printing processes as being used in 3D printing technology, but here the part printed with smart materials change their shape with time or by the change of environmental temperature, which further creates innovation for patient treatments. 4D printing manufactures a given part, layer by layer, by taking input of a virtual (CAD) model and uses smart material. This paper studies the capability of smart materials and their advancements when used in 4D printing. We have diagrammatically presented the significant parts of 4D printing technology. This paper identifies 11 significant applications of 4D printing and then studies which one provides innovative solutions during the COVID-19 pandemic.

Download Full-text

The Emerging Role of Decellularized Plant-Based Scaffolds as a New Biomaterial

International Journal of Molecular Sciences ◽

10.3390/ijms222212347 ◽

2021 ◽

Vol 22 (22) ◽

pp. 12347

Author(s):

Ashlee F. Harris ◽

Jerome Lacombe ◽

Frederic Zenhausern

Keyword(s):

Mechanical Properties ◽

Fruits And Vegetables ◽

Low Cost ◽

Three Dimensional ◽

Structural Features ◽

Cellular Models ◽

Current State ◽

Wide Range ◽

Future Challenges

The decellularization of plant-based biomaterials to generate tissue-engineered substitutes or in vitro cellular models has significantly increased in recent years. These vegetal tissues can be sourced from plant leaves and stems or fruits and vegetables, making them a low-cost, accessible, and sustainable resource from which to generate three-dimensional scaffolds. Each construct is distinct, representing a wide range of architectural and mechanical properties as well as innate vasculature networks. Based on the rapid rise in interest, this review aims to detail the current state of the art and presents the future challenges and perspectives of these unique biomaterials. First, we consider the different existing decellularization techniques, including chemical, detergent-free, enzymatic, and supercritical fluid approaches that are used to generate such scaffolds and examine how these protocols can be selected based on plant cellularity. We next examine strategies for cell seeding onto the plant-derived constructs and the importance of the different functionalization methods used to assist in cell adhesion and promote cell viability. Finally, we discuss how their structural features, such as inherent vasculature, porosity, morphology, and mechanical properties (i.e., stiffness, elasticity, etc.) position plant-based scaffolds as a unique biomaterial and drive their use for specific downstream applications. The main challenges in the field are presented throughout the discussion, and future directions are proposed to help improve the development and use of vegetal constructs in biomedical research.

Download Full-text

3D Printing of Thermoplastic Elastomers: Role of the Chemical Composition and Printing Parameters in the Production of Parts with Controlled Energy Absorption and Damping Capacity

Polymers ◽

10.3390/polym13203551 ◽

2021 ◽

Vol 13 (20) ◽

pp. 3551

Author(s):

Marina León-Calero ◽

Sara Catherine Reyburn Valés ◽

Ángel Marcos-Fernández ◽

Juan Rodríguez-Hernandez

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

3D Printing ◽

Energy Absorption ◽

Thermoplastic Elastomers ◽

Damping Capacity ◽

Compression Tests ◽

Wide Range ◽

Printing Parameters

Additive manufacturing (AM) is a disruptive technology that enables one to manufacture complex structures reducing both time and manufacturing cost. Among the materials commonly used for AM, thermoplastic elastomers (TPE) are of high interest due to their energy absorption capacity, energy efficiency, cushion factor or damping capacity. Previous investigations have exclusively focused on the optimization of the printing parameters of commercial TPE filaments and the structures to analyse the mechanical properties of the 3D printed parts. In the present paper, the chemical, thermal and mechanical properties for a wide range of commercial thermoplastic polyurethanes (TPU) filaments were investigated. For this purpose, TGA, DSC, 1H-NMR and filament tensile strength experiments were carried out in order to determine the materials characteristics. In addition, compression tests have been carried out to tailor the mechanical properties depending on the 3D printing parameters such as: infill density (10, 20, 50, 80 and 100%) and infill pattern (gyroid, honeycomb and grid). The compression tests were also employed to calculate the specific energy absorption (SEA) and specific damping capacity (SDC) of the materials in order to establish the role of the chemical composition and the geometrical characteristics (infill density and type of infill pattern) on the final properties of the printed part. As a result, optimal SEA and SDC performances were obtained for a honeycomb pattern at a 50% of infill density.

Download Full-text

Study of Mechanical Properties of 3D Printed Material for Non-Pneumatic Tire Spoke

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.880.97 ◽

2021 ◽

Vol 880 ◽

pp. 97-102

Author(s):

Ravivat Rugsaj ◽

Chakrit Suvanjumrat

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Elastic Material ◽

Molding Process ◽

Breaking Strain ◽

Pneumatic Tire ◽

Wide Range ◽

Printing Technique ◽

3D Printed ◽

3D Printing Technique

The spokes of airless tire or non-pneumatic tire (NPT) are normally made with thermoplastic polyurethane (TPU), which is highly elastic material, to replace inflation pressure in conventional pneumatic tire. However there are limitation in designing of complex spoke geometries due to difficulty in manufacturing process, which normally involve molding process. Recently, the 3D printing technique has been improved and can be used to create highly complex geometries with wide range of materials. However the mechanical properties of printed spoke structure using 3D printing technique are still required to design and development of NPT. This research aim to study the mechanical properties of TPU while varying in printing conditions. The specimens were prepared from actual NPT spoke using waterjet cutting technique and 3D printing technique according to the testing standard ASTM D412 and D638, respectively. The tensile tests were performed on the specimens with corresponding crosshead speed. The testing speed of 3D printed specimen were also varied to 100 and 200 mm/min to study the effects of strain rate on mechanical properties. The stress-strain relationships were obtained from tensile testing and the important mechanical properties were then evaluated. The mechanical properties of specimens prepared from actual NPT spokes and 3D printed specimens were then compared. The ultimate stress of specimens prepared from actual NPT spokes in radial direction and 3D printed specimens with 100% infill were found to be 32.92 and 25.47 MPa, respectively, while the breaking strain were found to be 12.98 and 10.87, respectively. Thus, the information obtained from this research can be used to ensure the possibility in creating NPT spoke using 3D printing technique based on elastic material such as TPU.

Download Full-text

Rheological and Mechanical Gradient Properties of Polyurethane Elastomers for 3D-Printing with Reactive Additives

Applied Rheology ◽

10.1515/arh-2019-0014 ◽

2019 ◽

Vol 29 (1) ◽

pp. 162-172

Author(s):

Peng Wang ◽

Dietmar Auhl ◽

Eckart Uhlmann ◽

Georg Gerlitzky ◽

Manfred H. Wagner

Keyword(s):

Mechanical Properties ◽

Reaction Time ◽

3D Printing ◽

Loss Modulus ◽

Polyurethane Elastomers ◽

Small Amplitude Oscillatory Shear ◽

Wide Range ◽

Reactive Additives ◽

Kinetics Of ◽

Reaction Speed

Abstract Polyurethane (PU) elastomers with their broad range of strength and elasticity are ideal materials for additive manufacturing of shapes with gradients of mechanical properties. By adjusting the mixing ratio of different polyurethane reactants during 3D-printing it is possible to change the mechanical properties. However, to guarantee intra- and inter-layer adhesion, it is essential to know the reaction kinetics of the polyurethane reaction, and to be able to influence the reaction speed in a wide range. In this study, the effect of adding three different catalysts and two inhibitors to the reaction of polyurethane elastomers were studied by comparing the time of crossover points between storage and loss modulus G′ and G′′ from time sweep tests of small amplitude oscillatory shear at 30°C. The time of crossover points is reduced with the increasing amount of catalysts, but only the reaction time with one inhibitor is significantly delayed. The reaction time of 90% NCO group conversion calculated from the FTIR-spectrum also demonstrates the kinetics of samples with different catalysts. In addition, the relation between the conversion as determined from FTIR spectroscopy and the mechanical properties of the materials was established. Based on these results, it is possible to select optimized catalysts and inhibitors for polyurethane 3D-printing of materials with gradients of mechanical properties.

Download Full-text

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

Journal of Materials Science ◽

10.1007/s10853-021-06811-3 ◽

2022 ◽

Author(s):

Marcos García Reyes ◽

Alex Bataller Torras ◽

Juan A. Cabrera Carrillo ◽

Juan M. Velasco García ◽

Juan J. Castillo Aguilar

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Biocompatible Materials ◽

Rupture Stress ◽

Bending Tests ◽

Wide Range ◽

3D Printers ◽

Materials Used ◽

Manufacturing Technologies ◽

Printing Direction

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.

Download Full-text