Numerical simulation and printability analysis of fused deposition modeling with dual-temperature control

Ideal tissue engineering scaffolds need interconnected pores and high porosity to enable cell survival,migration,proliferation,and differentiation.However,obtaining a high-resolution structure is difficult with traditional one-temperature control fused deposition modeling(FDM).In this study,we propose a dual-temperature control method to improve printability.A numerical model is developed in which the viscosity is a function of temperature and shear rate to study the influence of two different temperature control modes.Quantitative tests are used to assess filament formation and shape fidelity,including one-dimensional filament printing,deposition at corners,fusion,and collapse.By using dual-temperature control,the width of the deposited poly(ε-caprolactone)filament is reduced to 50μm.The comparative results of both the experimental method and numerical simulation suggest that the dual-temperature control FDM can manufacture spatially arranged constructs and presents a promising application in tissue engineering。

Effect of Fibre Size on Mechanical Properties and Surface Roughness of PLA Composites by Using Fused Deposition Modelling (FDM)

Naturalfibre as a reinforcing agent has been widely used in many industrial applications.Nevertheless,several factors need to be considered,such as the size and weight percentage of thefibre used in binding.Using fused deposition modelling(FDM),this factor was investigated by varying the size of naturalfibre as the responding variable with afixed weight percentage of kenaffibre.The process of modifying the naturalfibre in terms of size might increase the dispersion of kenaffibre in the polymer matrix and increase the adhesion bonding between thefibre and matrix of composites,subsequently improving the interfacial bonding between these two phases.In this paper,the effect offibre size was evaluated by performing the mechanical test,Scanning Electron Micrograph(SEM)to observe the morphology of the composites,and also by surface analysis.The surface roughness was visualised using a 3D profilometer and thefigure was illustrated as colour shading in the image.The composite withfibre size≤100μm displayed better tensile andflexural strength,compared to other sizes.In conclusion,by reducing the size of thefibre,the composites could develop high strength performance for industrial applications.

Comparison of wear behavior of ABS and Nylon6-Fe powder composite parts prepared with fused deposition modelling

Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study the friction and wear behavior of parts made of newly developed Nylon6-Fe composite material by FDM. This work also involves the comparison of the friction and wear characteristics of the Nylon6-Fe composite with the existing acrylonitrile butadiene styrene(ABS) filament of the FDM machine. This Is carried out on the pin on disk setup by varying the load(5, 10, 15 and 20 N) and speed(200 and 300 r/min). It is concluded that the newly developed composite is highly wear resistant and can be used in industrial applications where wear resistance is of paramount importance. Morphology of the surface in contact with the Nylon6-Fe composite and ABS is also carried out.

Optimization of Fused Deposition Modelling (FDM) Process Parameters Using Bacterial Foraging Technique

Fused deposition modelling (FDM) is a fast growing rapid prototyping (RP) technology due to its ability to build functional parts having complex geometrical shapes in reasonable build time. The dimensional accuracy, surface roughness, mechanical strength and above all functionality of built parts are dependent on many process variables and their settings. In this study, five important process parameters such as layer thickness, orientation, raster angle, raster width and air gap have been considered to study their effects on three responses viz., tensile, flexural and impact strength of test specimen. Experiments have been conducted using central composite design (CCD) and empirical models relating each response and process parameters have been developed. The models are validated using analysis of variance (ANOVA). Finally, bacterial foraging technique is used to suggest theoretical combination of parameter settings to achieve good strength simultaneously for all responses.

A fiber Bragg grating based earth and water pressures transducer with three-dimensional fused deposition modeling for soil mass

A novel fiber Bragg grating(FBG)sensor with three-dimensional(3D)fused deposition modeling(FDM)approach is proposed for effective stress measurement in soil mass.The three-diaphragm structure design is developed to measure earth and water pressures simultaneously.The proposed transducer has advantages of small size,high sensitivity,low cost,immunity to electromagnetic interference and rapid prototyping.The working principle,design parameters,and manufacturing details are discussed.The proposed transducer was calibrated for earth and water pressures measurement by using weights and a specially designed pressure chamber,respectively.The calibration results showed that the wavelength of the transducer was proportional to the applied pressure.The sensitivity coefficients of the earth and water pressures were 12.633 nm/MPa and 6.282 nm/MPa,respectively.Repeated tests and error analysis demonstrated the excellent stability and accuracy of the earth and water pressure measurements.The performance of the proposed transducer was further verified by a model experimental test and numerical analysis,which indicated that the proposed transducer has great potential for practical applications.

Design and Manufacturing Strategies for Fused Deposition Modelling in Additive Manufacturing:A Review

Although several research works in the literature have focused on studying the capabilities of additive manufacturing(AM) systems, few works have addressed the development of Design for Additive Manufacturing(DfAM) knowledge,tools, rules, and methodologies, which has limited the penetration and impact of AM in industry. In this paper a comprehensive review of design and manufacturing strategies for Fused Deposition Modelling(FDM) is presented.Consequently, several DfAM strategies are proposed and analysed based on existing research works and the operation principles, materials, capabilities and limitations of the FDM process. These strategies have been divided into four main groups: geometry, quality, materials and sustainability. The implementation and practicality of the proposed DfAM is illustrated by three case studies. The new proposed DfAM strategies are intended to assist designers and manufacturers when making decisions to satisfy functional needs, while ensuring manufacturability in FDM systems.Moreover, many of these strategies can be applied or extended to other AM processes besides FDM.

Surface Roughness Quality and Dimensional Accuracy—A Comprehensive Analysis of 100% Infill Printed Parts Fabricated by a Personal/Desktop Cost-Effective FDM 3D Printer

Fused deposition modeling (FDM) has become widely used for personal/ desktop cost-effective printers. This work presents an investigational platform, which is used to study the surface roughness quality, and dimensional accuracy of 100% infill density printed parts fabricated by a personal/desktop cost-effective FDM 3D printer using different types of thermoplastic filament materials namely, PLA, PLA+, ABS and ABS+. Varieties of experiments were conducted after the fabricated parts were naturally cooled down for at least three hours to room temperature. During printing work, the nozzle diameter, layer height, nozzle temperature and printing speed were set at 0.3 mm, 0.1 mm, 220°C and 30 mm/s, respectively. According to the experimentally obtained data results over 10 mm scanned profile and 90°measuring direction (perpendicular to building direction), PLA+ thermoplastic filament material shows an excellent surface behaviour and is found to be more accurate while ABS does exhibit high surface roughness, waviness and primary behaviour. Both PLA and ABS+ show good surface performance.

Mechanical characteristics of oil palm fiber reinforced thermoplastics as filament for fused deposition modeling(FDM)

Fibers are increasingly in demand for a wide range of polymer composite materials.This study^purpose was the development of oil palm fiber(OPF)mixed with the thermoplastic material acrylonitrile butadiene styrene(ABS)as a composite filament for fused deposition modeling(FDM).The mechanical properties of this composite filament were then analyzed.OPF is a fiber extracted from empty fruit bunches,which has proved to be an excellent raw material for biocomposites.The cellulose content of OPF is 43%-65%,and the lignin content is 13%-25%.The composite lilament consists of OPF(5%,mass fraction)in the ABS matrix.The fabrication procedure included alkalinizing,drying,and crushing the OPF to develop the composite.The OPF/ABS materials were prepared and completely blended to acquire a mix of 250 g of the material for the composition.Next,the FLD25 filament extrusion machine was used to form the OPF/ABS composite into a wire.This composite filament then was used in an FDM-based 3D printer to print the specimens.Finally,the printed specimens were tested for mechanical properties such as tensile and flexural strength.The results show that the presence of OPF had increased the tensile strength and modulus elasticity by approximately 1.9%and 1.05%,respectively.However,the flexural strength of the OPF/ABS composite had decreased by 90.6%compared with the virgin ABS.Lastly,the most significant outcome of the OPF/ABS composite was its suitability for printing using the FDM method.

Optimization of fused deposition modeling process parameters:a review of current research and future prospects

Fused deposition modeling （FDM） is one of the most popuIar additive manufacturing technologies for various engineering applications. FDM process has been introduced commercially in early 1990s by Stratasys Inc., USA. The quality of FDM processed parts mainly depends on careful selection of process variables. Thus, identifica- tion of the FDM process parameters that significantly affect the quality of FDM processed parts is important. In recent years, researchers have explored a number of ways to improve the mechanical properties and part quality using various experimental design techniques and concepts. This article aims to review the research carried out so far in determining and optimizing the process parameters of the FDM process. Several statistical designs of experiments and optimization techniques used for the determination of optimum process parameters have been examined. The trends for future FDM research in this area are described.

Optimization of fused deposition modeling process parameters using a fuzzy inference system coupled with Taguchi philosophy

Fused deposition modeling （FDM） is an additive manufacturing technique used to fabricate intricate parts in 3D, within the shortest possible time without using tools, dies, fixtures, or human intervention. This article empiri- cally reports the effects of the process parameters, i.e., the layer thickness, raster angle, raster width, air gap, part orientation, and their interactions on the accuracy of the length, width, and thicknes, of acrylonitrile-butadiene- styrene （ABSP 400） parts fabricated using the FDM tech- nique. It was found that contraction prevailed along the directions of the length and width, whereas the thickness increased from the desired value of the fabricated part. Optimum parameter settings to minimize the responses, such as the change in length, width, and thickness of the test specimen, have been determined using Taguchi＇s parameter design. Because Taguchi＇s philosophy fails to obtain uniform optimal factor settings for each response, in this study, a fuzzy inference system combined with the Taguchi philosophy has been adopted to generate a single response from three responses, to reach the specific target values with the overall optimum factor level settings. Further, Taguchi and artificial neural network predictive models are also presented in this study for an accuracy evaluation within the dimensions of the FDM fabricated parts, subjected to various operating conditions. The pre- dicted values obtained from both models are in good agreement with the values from the experiment data, with mean absolute percentage errors of 3.16 and 0.15, respectively. Finally, the confirmatory test results showed an improvement in the multi-response performance index of 0.454 when using the optimal FDM parameters over the initial values.

Filament geometrical model and nozzle trajectory analysis in the fused deposition modeling process

The geometrical model of the filament during the fused deposition modeling (FDM) process was firstly proposed based on three different models, tractrix, parabola, and catenary. Comparing with the actual measured filament curves on the Stratasys 1600 FDM machine, it is indicated that the tractrix model had the best agreement with the actual measured curves. With the analytical simulation, the nozzle trajectories in the straight-line deposition road, circle road, and arbitrary continuous curve road were deduced, according to the traxtric based geometrical model of the filament.

FDMS工艺制备金刚石工具技术浅析

近些年,熔融沉积成形烧结(fused deposition modeling sintering,FDMS)技术迅猛发展,由于其具有能耗低、打印稳定性高、成形设备价格低廉和操作简单等优点,在金刚石工具的制造中具有巨大的发展潜力。对FDMS工艺制备金刚石工具的技术可行性进行了分析,系统论述了FDMS技术的制备工艺流程、打印参数优选以及打印设备优化设计等内容,列举了FDMS制造金刚石超薄片的研究成果,指出了FDMS技术在制造金刚石工具中的关键问题,并对其发展进行了展望。

A Study of Melt Flow Analysis of an ABS-Iron Composite in Fused Deposition Modelling Process

Fused deposition modelling (FDM) is a filament based rapid prototyping system which offers the possibility of introducing new composite material for the FDM process as long as the new material can be made in feedstock filament form. Swinburne has been undertaking extensive research in development of new composite materials involving acrylonitrile-butadiene-styrene (ABS) and other materials including metals. In order to predict the behaviour of new ABS based composite materials in the course of FDM process, it is necessary to investigate the flow of the composite material in liquefier head. No such study is available considering the geometry of the liquefier head. This paper presents 2-D and 3-D numerical analysis of melt flow behaviour of a representative ABS-iron composite through the 90-degree bent tube of the liquefier head of the fused deposition modelling process using ANSYS FLOTRAN and CFX finite element packages. Main flow parameters including temperature, velocity, and pressure drop have been investigated. Filaments of the filled ABS have been fabricated and characterized to verify the possibility of prototyping using the new material on the current FDM machine. Results provide promising information in developing the melt flow modelling of metal-plastic composites and in optimising the FDM parameters for better part quality with such composites.

Analysis on fused deposition modelling performance

Fused deposition modelling (FDM) is one of rapid prototyping (RP) technologies which uses an additive fabrication approach.Each commercially available FDM model has different types of process parameters for different applications.Some of the desired parts require excellent surface finish as well as good tolerance.The most common parameters requiring setup are the raster angle,tool path,slice thickness,build orientation,and deposition speed.The purpose of this paper is to discuss the process parameters of FDM Prodigy Plus (Stratasys,Inc.,Eden Prairie,MN,USA).Various selected parameters were tested and the optimum condition was proposed.The quality of the parts produced was accessed in terms of dimensional accuracy and surface finish.The optimum parameters obtained were then applied in the fabrication of the master pattern prior to silicone rubber moulding (SRM).These parameters would reduce the post processing time.The dimensional accuracy and surface roughness were analyzed using coordinate measuring machine (CMM) and surface roughness tester,respectively.Based on this study,the recommended parameters will improve the quality of the FDM parts produced in terms of dimensional accuracy and surface roughness for the application of SRM.

Tribological behaviour of fused deposition modelling printed short carbon fibre reinforced nylon composites with surface textures under dry and water lubricated conditions

Fused deposition modelling(FDM)printed short carbon fibre reinforced nylon(SCFRN)composites were fabricated.The friction and wear behaviour of printed materials were systematically investigated under both dry sliding and water lubricated conditions.The results showed that with short fibre enhancements,the printed SCFRN achieved a lower friction coefficient and higher wear resistance than nylon under all tested conditions.Further,under water lubricated conditions,the printed SCFRN exhibited a low,stable friction coefficient due to the cooling and lubricating effects of water.However,the specific wear rate of the printed specimens could be higher than that obtained under dry sliding conditions,especially when the load was relatively low.The square textured surface was designed and created in the printing process to improve materials’tribological performance.It was found that with the textured surface,the wear resistance of the printed SCFRN was improved under dry sliding conditions,which could be explained by the debris collection or cleaning effect of surface texture.However,such a cleaning effect was less noticeable under lubricated conditions,as the liquid could clean the surface effectively.On the other hand,surface textures could increase the surface area exposed to water,causing surface softening due to the higher water absorption rate.As a result,the samples having surface textures showed higher wear rates under lubricated conditions.The work has provided new insights into designing wear resistant polymer materials using three-dimensional(3D)printing technologies,subjected to different sliding conditions.

Modeling, analysis, and optimization of dimensional accuracy of FDM-fabricated parts using definitive screening design and deep learning feedforward artificial neural network

Additive manufacturing(AM)technologies such as fused deposition modeling(FDM)rely on the quality of manufactured products and the process capability.Currently,the dimensional accuracy and stability of any AM process is essential for ensuring that customer specifications are satisfied at the highest standard,and variations are controlled without significantly affecting the functioning of processes,machines,and product structures.This study aims to investigate the effects of FDM fabrication conditions on the dimensional accuracy of cylindrical parts.In this study,a new class of experimental design techniques for integrated second-order definitive screening design(DSD)and an artificial neural network(ANN)are proposed for designing experiments to evaluate and predict the effects of six important operating variables.By determining the optimum fabrication conditions to obtain better dimensional accuracies for cylindrical parts,the time consumption and number of complex experiments are reduced considerably in this study.The optimum fabrication conditions generated through a second-order DSD are verified with experimental measurements.The results indicate that the slice thickness,part print direction,and number of perimeters significantly affect the percentage of length difference,whereas the percentage of diameter difference is significantly affected by the raster-to-raster air gap,bead width,number of perimeters,and part print direction.Furthermore,the results demonstrate that a second-order DSD integrated with an ANN is a more attractive and promising methodology for AM applications.

FDM工艺过程中丝材的粘结机理与热学分析

分析了熔融堆积成形(FDM)工艺中挤出丝材的温度随时间、路径的变化规律,通过对丝材物理模型的合理假设,建立了挤出丝材温度场的数学模型,并根据Stratasys商用机FDM2000所使用的ABS-P400丝材的热学参数,结合聚合物的粘结机理,验证了模型的合理性.

FDM工艺出丝模型及补偿方法的研究

在研究 FDM工艺喷头挤出丝截面形状的基础上 ,建立了理想轮廓线的补偿模型 ,并通过实例对该模型进行了验证。提出了根据挤出丝实际宽度 (而非喷嘴孔直径 )和零件尺寸实际收缩量补偿零件内外轮廓的新方法 ,即不仅要考虑材料收缩对零件“宏观”尺寸的影响 ,而且还需考虑材料收缩对“微观”尺寸——挤出丝截面宽度的影响。验证试验结果表明 ,应用所提出的补偿方法能对 FDM工艺原型尺寸进行正确补偿。

FDM快速成型技术在动漫模型制作中的应用

由于传统加工无法满足动漫模型形状复杂、单件小批量,制作周期短,而3D打印技术中的FDM快速成型技术可以解决这些问题。根据FDM快速成型技术成本低、体积小、无污染以及制作速度快的特点,利用简易型快速成型机完成了一批客户急需的动漫模型的制作。针对模型在制作过程中由加工设备、加工参数等因素产生的冷却收缩变形以及开裂等缺陷进行了分析。提出了对模型抽壳或者掏空的方案减小了模型的冷却收缩变形,优化了加工工艺参数以提高模型的质量和制作的效率。