Fused Deposition Modeling Technique Research Articles

Bioinspired poly-dopamine/nano-hydroxyapatite: an upgrading biocompatible coat for 3D-printed polylactic acid scaffold for bone regeneration.

Poly-lactic acid (PLA) has been proposed in dentistry for several regenerative procedures owing to its biocompatibility and biodegradability. However, the presence of methyl groups renders PLA hydrophobic, making the surface less ideal for cell attachment, and it does not promote tissue regeneration. Upgrading PLA with inductive biomaterial is a crucial step to increase the bioactivity of the PLA and allow cellular adhesion. Our purpose is to evaluate biocompatibility, bioactivity, cellular adhesion, and mechanical properties of 3D-printed PLA scaffold coated with poly-dopamine (PDA) and nano-hydroxyapatite (n-HA) versus PLA and PLA/n-HA scaffolds. The fused deposition modelling technique was used to print PLA, PLA with embedded n-HA particles, and PLA scaffold coated with PDA/n-HA by immersion. After matrices characterization for their chemical composition and surface properties, testing the compressive strength was pursued using a universal testing machine. The bioactivity of scaffolds was evaluated by monitoring the formation of calcium phosphate compounds after simulated body fluid immersion. The PLA/PDA/n-HA scaffold showed the highest compressive strength which was 29.11 ± 7.58 MPa with enhancing calcium phosphate crystals deposition with a specific calcium polyphosphate phase formed exclusively on PLA/PDA/n-HA. With cell viability assay, the PDA/n-HA-coated matrix was biocompatible with increase in the IC50, reaching ⁓176.8 at 72 without cytotoxic effect on the mesenchymal stem cells, promoting their adhesion and proliferation evaluated by confocal microscopy. The study explored the biocompatibility, bioactivity, and the cell adhesion ability of PDA/n-HA coat on a 3D-printed PLA scaffold that qualifies its use as a promising regenerative material.

Researching on the Effect of Input Parameters on the Quality and Manufacturability of 3D-Printed Cellular Samples from Nylon 12 CF in Synergy with Testing Their Behavior in Bending.

The study of cellular structures and their properties represents big potential for their future applications in real practice. The article aims to study the effect of input parameters on the quality and manufacturability of cellular samples 3D-printed from Nylon 12 CF in synergy with testing their bending behavior. Three types of structures (Schwarz Diamond, Shoen Gyroid, and Schwarz Primitive) were selected for investigation that were made via the fused deposition modeling technique. As part of the research focused on the settings of input parameters in terms of the quality and manufacturability of the samples, input parameters such as volume fraction, temperature of the working space, filament feeding method and positioning of the sample on the printing pad were specified for the combination of the used material and 3D printer. During the experimental investigation of the bending properties of the samples, a three-point bending test was performed. The dependences of force on deflection were mathematically described and the amount of absorbed energy and ductility were evaluated. The results show that among the investigated structures, the Schwarz Diamond structure appears to be the most suitable for bending stress applications.

Enhanced Bone Healing in Critical-Sized Rabbit Femoral Defects: Impact of Helical and Alternate Scaffold Architectures.

This study investigates the effect of scaffold architecture on bone regeneration, focusing on 3D-printed polylactic acid-bioceramic calcium phosphate (PLA-bioCaP) composite scaffolds in rabbit femoral condyle critical defects. We explored two distinct scaffold designs to assess their influence on bone healing and scaffold performance. Structures with alternate (0°/90°) and helical (0°/45°/90°/135°/180°) laydown patterns were manufactured with a 3D printer using a fused deposition modeling technique. The scaffolds were meticulously characterized for pore size, strut thickness, porosity, pore accessibility, and mechanical properties. The in vivo efficacy of these scaffolds was evaluated using a femoral condyle critical defect model in eight skeletally mature New Zealand White rabbits. Then, the results were analyzed micro-tomographically, histologically, and histomorphometrically. Our findings indicate that both scaffold architectures are biocompatible and support bone formation. The helical scaffolds, characterized by larger pore sizes and higher porosity, demonstrated significantly greater bone regeneration than the alternate structures. However, their lower mechanical strength presented limitations for use in load-bearing sites.

Investigating the impact of laser polishing parameters on surface roughness, mass ablation rate, and optical transmittance of 3D‐printed PLA substrates

AbstractLaser polishing technique is one of the most effective post‐processing methods for 3D‐printed Polylactic acid (PLA) substrates and has gained significant interest of scientific research community in past few years. This paper aims to investigate the effect of fill density, laser power, and scanning speed on the polishing responses of 3D‐printed PLA substrates. These include surface roughness, mass ablation rate, and optical transmittance of PLA substrates printed using the fused deposition modeling technique. The optical transmittance was measured using Fourier‐transform infrared spectroscopy technique and surfaces were characterized using scanning electron microscope, and optical microscope. Minimum surface roughness of 1.04 μm was achieved at 5% laser power and 55% fill density constituting a decrease of 61.8% from unpolished PLA (2.735 μm). The lowest mass ablation rate (0.015 μg/pulse) was observed for the specimens with 40% infill density. Higher scanning speed enhanced the molecular bonding in PLA‐55 specimen indicated by increased peak transmittance ratios of CH bonds at stretching (1.021) and bending modes (1.045).

A novel pellet-based 3D printing of high stretchable elastomer

Elastomers, known for their high stretchability and flexibility, are widely used in high-tech applications. However, traditional manufacturing methods for elastomeric part production have limitations. 3D printing, particularly fused deposition modeling (FDM), offers a promising alternative by allowing the fabrication of customized elastomers with desired shapes and properties. Conventional filament-based FDM techniques struggle to print elastomers. This article presents a novel approach for 3D printing polyolefin elastomer (POE) using a direct pellet printing technique. A customized pellet printer with a pneumatic pressure feeding system was used that eliminates filament buckling issues commonly associated with conventional filament-based 3D printing methods. The mechanical properties and microstructure of the printed parts were analyzed to evaluate the suitability of the technique for producing high-quality elastomeric components. SEM images indicated a high-quality and accurate printing method; however, there are micro-holes between the raster due to the high shrinkage rate of POE and increasing the nozzle temperature improves the print quality. The mechanical properties of the printed samples exhibited remarkable formability, with elongation reaching up to 1965%. It is also found that as the nozzle temperature increased, the strength, elongation, and bonding between layers improved significantly. This innovative 3D printing technique has the potential for various applications such as soft robotics and wearable electronics.

Compressive properties of a modified re-entrant chiral auxetic structure (MRCA) under uniaxial quasi-static loading

Auxetics are a unique class of innovative materials/structures. Auxetic material/structures possess a negative value of Poisson’s ratio owing to the distinguished deformation behavior represented by the transvers expansion or contraction when they experience uniaxial stretching or compression, respectively. The aim of this manuscript is to show contributions of the structural modification on an auxetic hybrid structure. The in-plane properties of an auxetic structure, called the modified re-entrant chiral auxetic (MRCA) structure under quasi-static compression were experimentally and numerically explored. The experimental specimens were 3D printed using fused deposition modeling technique. The commercial ABAQUS/Explicit solver was used to develop the simulated models. Results showed that the structural modification have led to effectively improve deformation coordination (i.e. uniform deformation patterns) and the compressive properties of the modified structure. Young’s moduli were 1.75 and 12.7 higher than those of the original geometry, while values of plateau stress were 3.1 and 1.23 higher than those of the original geometry when they were compressed along the X and Y axes, respectively. The specific energy absorptions per unit mass were 4.7 J g−1 and 3.9 J g−1 when the MRCA specimens were compressed along the X and Y axes, respectively. However, the added cylinders limited the auxeticity (i.e. the transvers contraction) of the specimens during the compression tests.

Topology optimization and 3D printing of a unibody quadcopter airframe

The performance of any unmanned aerial vehicle largely depends upon its weight as this characteristic dictates its payload capacity and flight duration. This paper presents a multiphysics simulation method for designing a unibody quadcopter airframe with optimum weight in SolidWorks. By adopting the computer-aided topology optimization concept, the mass of the frame is decreased by 91% (from 1558.44 to 134.738 grams) after getting rid of the unwanted elements, while not compromising its structural rigidity. The efficacy of the model is assessed by finite element analysis and it is found that the stress would remain within the acceptable limit. The optimized structure shows an operating life of 1.6×105 cycles in the fatigue analysis and experiences significantly less drag force in the computational fluid dynamics test than the original airframe for several angles of attack, thus proving the superiority of the optimized frame over the initial model. Finally, additive manufacturing is performed to fabricate the optimized structure using PLA material. 3D printing through the fused deposition modeling technique is chosen since it is ideal for fabricating intricate engineering prototypes compared to orthodox manufacturing processes. While creating the frame, a 45° overhang angle is maintained to ensure the usage of less support material.

Bioactive materials‐coated polybutylene‐adipate‐co‐terephthalate 3D‐printed scaffolds for application in the bone tissues engineering

AbstractBone tissue engineering (BTE) is a biomedical area that develops scaffolds capable of mimicking and repairing damage on bone tissue. For this, a popular and nonexpensive 3D printing technique named fused deposition modeling (FDM) has been used. The potential use of 3D scaffolds of poly(butylene adipate‐co‐terephthalate (PBAT) has been investigated in BTE since this polymer presents good biocompatibility and degradability, as well as mechanical properties like those offered by the natural bone. A single material does not have the features to promote cell adhesion, proliferation, and differentiation; the incorporation of bioactive substances can overcome this issue. This work aimed to develop 3D printed PBAT scaffolds by FDM technique and coated them with hydroxyapatite (H), bioglass (B), and gelatin (G) by solution immersion technique to obtain a functional biomaterial to be applied on the BTE. Structural characteristics and morphological and mechanical properties of the 3D scaffolds were evaluated. The cell proliferation and mineralization of pre‐osteoblastic cells (MC3T3‐E1) were accessed by methylthiazolyldiphenyl‐tetrazolium bromide, sulphorodhamine B, and Alizarin red assay, respectively. 3D printed PBAT scaffolds were successfully obtained by FDM, and the surface modification of 3D PBAT was proven through the changes observed in structural and morphological characteristics. In addition, the mechanical properties were improved in the modified scaffolds. Also, the coated 3D PBAT scaffolds with any bioactive substance increased and promoted cell proliferation and pre‐osteoblastic differentiation. Therefore, the combination of 3D PBAT scaffolds and H, G, and/or B (doped with niobium) is an alternative to produce functional biomaterials for BTE.

Investigation of the wear and friction profile of TPU-based polymers at different infill ratios

Additive manufacturing is a widely used method in industry and research areas. In particular, fused deposition modelling is the most prevalent technique used by many professional and nonprofessional users. Many polymers can be used with this system, including thermo polyurethanes (TPU). TPUs have excellent elastic properties and high endurance against corrosion, humidity, and oil, and they ex-hibit a great absorbance capability to noise and vibrations, biocompatibility, and chemical resistance. Thermoplastic polyurethane (TPU) is also preferred for use in 3D/4D printing applications due to its easy casting, injection, and extrusion capabilities and its shape memory features. In this study, flexible TPU and carbon-mixed TPU were used to produce specimens with fused deposition modelling tech-niques at different infill ratios with the same patterns. The effects of the infill ratio within the different and same materials were investigated in terms of wear and friction profiles. Additionally, thermal and worn surface images were taken using a digital microscope. The hardness and diameter value altera-tions were also investigated for different materials and infill ratios. As a result of the study, material al-teration is more effective than the infill ratios in all parameters.

Biocompatible Composite Filaments Printable by Fused Deposition Modelling Technique: Selection of Tuning Parameters by Influence of Biogenic Hydroxyapatite and Graphene Nanoplatelets Ratios.

The proposed strategy for the extrusion of printable composite filaments follows the favourable association of biogenic hydroxyapatite (HA) and graphene nanoplatelets (GNP) as reinforcement materials for a poly(lactic acid) (PLA) matrix. HA particles were chosen in the <40 μm range, while GNP were selected in the micrometric range. During the melt-mixing incorporation into the PLA matrix, both reinforcement ratios were simultaneously modulated for the first time at different increments. Cylindrical composite pellets/test samples were obtained only for the mechanical and wettability behaviour evaluation. The Fourier-transformed infrared spectroscopy depicted two levels of overlapping structures due to the solid molecular bond between all materials. Scanning electron microscopy and surface wettability and mechanical evaluations vouched for the (1) uniform/homogenous dispersion/embedding of HA particles up to the highest HA/GNP ratio, (2) physical adhesion at the HA-PLA interface due to the HA particles' porosity, (3) HA-GNP bonding, and (4) PLA-GNP synergy based on GNP complete exfoliation and dispersion into the matrix.

Mechanical behavior of interpenetrating phase composite structures based on triply periodic minimal surface lattices

The triple periodic minimal surface (TPMS) structures have received widespread attention due to their excellent mechanical properties, such as high specific strength and energy absorption. However, these structures are prone to suffering catastrophic damage due to stress concentration and shear deformation in actual loading environments, affecting their load-bearing performance. In this work, interpenetrating phase composite (IPC) structures were fabricated by filling thermoplastic polyurethane (TPU) as a soft material into the diamond minimal surface structure using the multi-material fused deposition modeling technique, and their mechanical behavior was investigated numerically and experimentally. The effects of topological types and volume fractions on the performance of IPC structures were investigated. It is shown that the IPC structure undergoes stretching-dominated deformation, and its strength and toughness are significantly improved compared to the TPMS structure. Due to the addition of a complementary phase structure made of TPU, stress concentration and shear failure are reduced. The global deformation of the IPC structure and stress distribution of the TPMS phase are more uniform, effectively protecting the entire structure from catastrophic failure.

Experimental study of the effect of different 3D printing parameters on tensile strength, using artificial neural network

Numerous research studies have been conducted to optimize printing parameters using the fused deposition modeling technique (FDM) to improve mechanical properties. The large number of process parameters creates a need to search for optimal combinations of parameters to improve mechanical properties. This study examines the effects of three parameters when printing 3D with melted filament of a PLA material (Polylactic Acid) on the ultimate tensile strength of the printed parts. This search combines an experimental study of the most influential printing parameters on the tensile strength property, namely layer thickness, printing temperature, and feed rate. The experimental results are then analyzed and modeled as a linear regression model. Then develop an intelligent artificial model based on ANN (Artificial Neural Network) derived from these experimental results capable of predicting the optimal combination of parameters providing maximum tensile strength. The observed results showed that the feed rate dominates among the other variables, followed by the thickness of the layer. Also, at the level of prediction, the artificial model provides a better prediction of the tensile strength with a value of 36.1625 MPa by combining the following parameters: Feed rate: 70 mm s−1, temperature: 200 °C, and layer thickness: 0.26 mm, compared to the prediction obtained by the linear regression model. Neural networks enable more accurate optimization of 3D process parameters, leading to an overall improvement in the quality of finished products. predictive models, significantly reducing the iteration time required to obtain optimal parameters. The quality of the data used to train neural networks is crucial.

Lap Shear Strength and Fatigue Analysis of Continuous Carbon-Fibre-Reinforced 3D-Printed Thermoplastic Composites by Varying the Load and Fibre Content.

This study focuses on evaluating the fatigue life performance of 3D-printed polymer composites produced through the fused deposition modelling (FDM) technique. Fatigue life assessment is essential in designing components for industries like aerospace, medical, and automotive, as it provides an estimate of the component's safe service life during operation. While there is a lack of detailed research on the fatigue behaviour of 3D-printed polymer composites, this paper aims to fill that gap. Fatigue tests were conducted on the 3D-printed polymer composites under various loading conditions, and static (tensile) tests were performed to determine their ultimate tensile strength. The fatigue testing load ranged from 80% to 98% of the total static load. The results showed that the fatigue life of the pressed samples using a platen press was significantly better than that of the non-pressed samples. Samples subjected to fatigue testing at 80% of the ultimate tensile strength (UTS) did not experience failure even after 1 million cycles, while samples tested at 90% of UTS failed after 50,000 cycles, with the failure being characterized as splitting and clamp area failure. This study also included a lap shear analysis of the 3D-printed samples, comparing those that were bonded using a two-part Araldite glue to those that were fabricated as a single piece using the Markforged Mark Two 3D printer. In summary, this study sheds light on the fatigue life performance of 3D-printed polymer composites fabricated using the FDM technique. The results suggest that the use of post-printing platen press improved the fatigue life of 3D-printed samples, and that single printed samples have better strength of about 265 MPa than adhesively bonded samples in which the strength was 56 MPa.

Effects of testing speed on the tensile and mode I fracture behavior of specimens printed through the Fused Deposition Modeling technique

Additive Manufacturing (AM) processes are known as revolutionary manufacturing processes that fabricate a part using a 3D model layer upon layer. These techniques gained more attention from various industries due to their advantages like low waste material. Also, these processes can produce any part with high degrees of complexity in a short period of time. The Fused Deposition Modeling (FDM) process is a material extrusion-based technique which works by extruding a fine molten polymeric filament through a heated nozzle on the heated platform named printer bed. In this method, some important manufacturing parameters play a crucial role in controlling the mechanical properties and quality of the final fabricated part. However, all printed specimens through the FDM process should be tested based on the standards under some critical circumstances. Thus, in the current research paper, five and three test speeds are considered in tensile and fracture testing procedures, respectively to evaluate how these speeds can affect the mechanical and mode I fracture properties. Also, as the FDM specimens present elastic–plastic behavior, the critical value of J-integral is assumed as a fracture assessment and calculated from the finite element analysis. Among the mechanical properties, ultimate tensile strength is affected significantly by the test speed. For instance, the ultimate tensile strength of FDM specimens is 39.02, 38.58, 42.33, 48.09, and 52.11 for test speeds of 2, 4, 6, 8, and 10 mm/min, respectively. But vice-versa results are detected for the mode I fracture behavior and corresponding values of J for the FDM-PLA specimens. Finally, experimental and numerical results together with comprehensive discussions about the considered speeds and obtained results are reported.

A new method of applying PLA coatings on the surface of magnesium alloy using the FDM technique

The subject of the work was presented a new method of applying PLA (polylactide) coatings on the magnesium alloy's surface using the FDM (Fused Deposition Modeling) technique. The aim of this work was develop a low-temperature, low-waste coating method of Mg alloy surface with a polymer layer with a repeatable, predictable morphology according to a previously assumed model that uniformly covers a metal element using FDM technique (patent number: PL239348). Until now, polymer layers on Mg alloys have been produced mainly by spin coating or dip coating. Both spin coating and dip coating methods do not guarantee even coverage of element's surface, especially on the edges. In addition, the surface morphology is not reproducible because it cannot be influenced directly during the layering process. The advanced coating technology for magnesium alloys presented in the paper is intended to be used as a technology for the production of protective layers for short-term resorbable orthopedic implants. Therefore, the influence of the thickness on the cohesion of the coating in the Ringer's solution of the tested Mg alloy-PLA system was assessed. The 240 μm thick polylactide coating on Mg alloy retained its integrity for 12 days of immersion in Ringer's Solution at 37 °C.The probable mechanism of PLA coating damage was also presented. The adhesive strength of the PLA - Mg alloy system is about 9 MPa. The biocompatibility was assessed by direct grown and proliferation assay on tested materials of normal human dermal fibroblasts (NHDF) and osteosarcoma cancer cells (U2OS). The microscopic observations confirm, that the surface modification's with a PLA coatings on magnesium alloy improves the materials and make them a good candidate for further applications in regenerative medicine.

Pore parameter selection for fused deposition modeling of gas diffusion layers in proton exchange membrane fuel cells

AbstractBecause of the global energy crisis, many researchers have focused their efforts on fuel cells. The gas diffusion layer (GDL) is a fundamental component of proton exchange membrane (PEM) fuel cells. The manufacturing procedures for traditional carbon‐based GDLs are sophisticated and energy‐intensive, and have design flexibility constraints, making it difficult to build complicated forms and structures. Additive manufacturing is widely used in a variety of fields, with the fused deposition modeling (FDM) technique being the most popular method. Prior to conducting systematic research on the printed GDLs, it is necessary to investigate the pore parameters with the support of FDM technique. In this research, the initial step involves material selection, FDM printer selection, and modeling. Subsequently, printing analysis and sample characterization are conducted to select an acceptable pore shape. A water drainage test determines the appropriate pore size, followed by additional tests for acceptable porosity range. The square pore shape is determined to be more suitable. A pore side length of 1.0 mm is identified. Furthermore, a suitable pore range of 10.9%–30.3% is identified. Next step, the printed GDLs will undergo further testing to investigate their suitability to be used in PEM fuel cells.

Architected tunable twist-compression coupling metastructures based on a generative parametric design for energy absorption and effective mechanical properties

Architected metamaterials are known as materials with unique mechanical and topological behavior. This paper presents architected twist-compression metamaterials, which twist around their axis under compression, for energy absorption and effective mechanical properties. The proposed metastrcutures are designed through novel generative algorithms that enable the parametric design in which the geometrical parameters of the produced metastructures are tunable. Several experimental tests were carried out to determine accurate material properties for the finite element analysis and to evaluate the capability of the presented metastructures. Specimens printed from acrylonitrile butadiene styrene (ABS) using fused deposition modeling techniques (FDM). To evaluate the effect of geometrical parameters on the properties of the twist-compression metastructures a four-step parametric study was conducted by virtue of the verified finite element models. These finite element models contain damage criteria to model the failure behavior of the metastrucutures under quasi-static loading. The influencing geometrical parameters on the mechanical properties, as well as energy absorption capacity, have been considered via numerical and experimental analysis. Obtained results showed some unique features of these structures in elastic and plastic behaviors.

Adaptable test bench for ASTM-compliant permeability measurement of porous scaffolds for tissue engineering

Intrinsic permeability describes the ability of a porous medium to be penetrated by a fluid. Considering porous scaffolds for tissue engineering (TE) applications, this macroscopic variable can strongly influence the transport of oxygen and nutrients, the cell seeding process, and the transmission of fluid forces to the cells, playing a crucial role in determining scaffold efficacy. Thus, accurately measuring the permeability of porous scaffolds could represent an essential step in their optimization process. In literature, several methods have been proposed to characterize scaffold permeability. Most of the currently adopted approaches to assess permeability limit their applicability to specific scaffold structures, hampering protocols standardization, and ultimately leading to incomparable results among different laboratories. The content of novelty of this study is in the proposal of an adaptable test bench and in defining a specific testing protocol, compliant with the ASTM International F2952-22 guidelines, for reliable and repeatable measurements of the intrinsic permeability of TE porous scaffolds. The developed permeability test bench (PTB) exploits the pump-based method, and it is composed of a modular permeability chamber integrated within a closed-loop hydraulic circuit, which includes a peristaltic pump and pressure sensors, recirculating demineralized water. A specific testing protocol was defined for characterizing the pressure drop associated with the scaffold under test, while minimizing the effects of uncertainty sources. To assess the operational capabilities and performance of the proposed test bench, permeability measurements were conducted on PLA scaffolds with regular (PS) and random (RS) micro-architecture and on commercial bovine bone matrix-derived scaffolds (CS) for bone TE. To validate the proposed approach, the scaffolds were as well characterized using an alternative test bench (ATB) based on acoustic measurements, implementing a blind randomized testing procedure. The consistency of the permeability values measured using both the test benches demonstrated the reliability of the proposed approach. A further validation of the PTB’s measurement reliability was provided by the agreement between the measured permeability values of the PS scaffolds and the theory-based predicted permeability value. Once validated the proposed PTB, the performed measurements allowed the investigation of the scaffolds’ transport properties. Samples with the same structure (guaranteed by the fused-deposition modeling technique) were characterized by similar permeability values, and CS and RS scaffolds showed permeability values in agreement with the values reported in the literature for bovine trabecular bone. In conclusion, the developed PTB and the proposed testing protocol allow the characterization of the intrinsic permeability of porous scaffolds of different types and dimensions under controlled flow regimes, representing a powerful tool in view of providing a reliable and repeatable framework for characterizing and optimizing scaffolds for TE applications.

Development of hybrid 3D printing approach for fabrication of high-strength hydroxyapatite bioscaffold using FDM and DLP techniques

This study develops a hybrid 3D printing approach that combines fused deposition modeling (FDM) and digital light processing (DLP) techniques for fabricating bioscaffolds, enabling rapid mass production. The FDM technique fabricates outer molds, while DLP prints struts for creating penetrating channels. By combining these components, hydroxyapatite (HA) bioscaffolds with different channel sizes (600, 800, and 1000 μm) and designed porosities (10%, 12.5%, and 15%) are fabricated using the slurry casting method with centrifugal vacuum defoaming for significant densification. This innovative method produces high-strength bioscaffolds with an overall porosity of 32%–37%, featuring tightly bound HA grains and a layered surface structure, resulting in remarkable cell viability and adhesion, along with minimal degradation rates and superior calcium phosphate deposition. The HA scaffolds show hardness ranging from 1.43 to 1.87 GPa, with increasing compressive strength as the designed porosity and channel size decrease. Compared to human cancellous bone at a similar porosity range of 30%–40%, exhibiting compressive strengths of 13–70 MPa and moduli of 0.8–8 GPa, the HA scaffolds demonstrate robust strengths ranging from 40 to 73 MPa, paired with lower moduli of 0.7–1.23 GPa. These attributes make them well-suited for cancellous bone repair, effectively mitigating issues like stress shielding and bone atrophy.

Design and Additive Manufacturing of a Prototype Using Fused Deposition Modeling Technique

A screw jack is a tool for lifting heavy loads with little effort. In this paper, the design, model and fabrication of a Screw jack using 3D Printing Technology is discussed. Digital fabrication, or 3D printing or additive manufacturing, creates physical objects from a geometrical representation by successive addition of materials. In agriculture, health care, motor vehicles, locomotives and aviation, 3D Printing is increasingly being applied for mass customization or production for all types of open-source design. Design is an important industrial activity which influences the quality of the product. The parts of a screw jack are modelled by using the modelling software Creo Parametric. The CAD model of the screw jack is then converted into. STL (Standard Tessellation Language) format in which the 3D Printer receives the printing input. The STL files are then imported to modelling software to analyze mesh and rectify errors. The rectified STL files of parts of the screw jack are imported to Makerbot software, and parts are made ready for 3D Printing using Makerbot FDM (Fused Deposition Modelling) 3D Printer. The parts printed in an FDM 3D printer are assembled based on the tolerances obtained, and the final prototype is fabricated.