Processing of Novel Electroceramic Components by SFF Techniques

1998 ◽  
Vol 542 ◽  
Author(s):  
A. Safari ◽  
S. C. Danforth ◽  
A. L. Kholkin ◽  
I. A. Cornejo ◽  
F. Mohammadi ◽  
...  

AbstractNovel piezoelectric ceramic and ceramic/polymer composite structures were fabricated by solid freeform fabrication (SFF) for sensor and actuator applications. SFF techniques including fused deposition of ceramics (FDC) and Sanders prototyping (SP) were utilized to fabricate a variety of complex structures directly from a computer aided design (CAD) file. Novel composite structures including volume fraction gradients (VFG) and staggered rods, as well as actuator designs such as tubes, spirals and telescopes were made using the flexibility provided by the above processes. VFG composites were made by SP technique with the ceramic content decreasing from the center towards the edges. This resulted in a reduction of side lobe intensity in the acoustic beam pattern. The FDC technique was used to manufacture high authority actuators utilizing novel designs for the amplification of strain under applied electric field. The design, fabrication and electromechanical properties of these composite and actuator structures are discussed in this paper.

Author(s):  
Zbigniew M. Bzymek ◽  
Wojciech Marks ◽  
Chandrasekhar Roychoudhuri ◽  
Lianchao Sun ◽  
Leon L. Shaw

Abstract Solid Freeform Fabrication (SFF) technologies refer to the fabrication of physical parts directly from computer-based solid models by layers using a row-by-row pattern, though it is possible to build the part using other patterns. The trend is to produce parts of 100% density which would have properties similar to those made by casting molten metal into a mold. Very good results have been obtained recently by treating a rendered part in a high pressure chamber. In this paper, an idea is presented in which the structure of a part can be designed in such a way that there is no need for the entire part to be 100% solid. The stresses are taken only by certain regions of structure and those regions should be rendered with full a density as possible. The rest of the part material is treated as filling and supporting substance which can be made as porous as is needed to conduct the heat out during the rendering process. In such an approach the design process for SFF technology would represent a challenge to designers who, in addition to making decisions concerning optimum shape and functionality of the entire part, have to take under consideration several other manufacturing factors. These factors cover a wide range of technical issues, such as Computer-Aided Design model generation, part description and model slicing files, laser path files, precision of part design, rendering patterns, manufacturing tolerances, thermal expansion, and residual stress phenomena. On the basis of experience gained in previously developed SFF part manufacturing, the authors describe the concepts and some conclusions from the research in progress that concentrates on two areas that are inseparable; developing the most suitable CAD methods for precise part design, and optimization of the part building structure for maximum part stiffness under a given load.


Author(s):  
Vikram R. Jamalabad ◽  
Mukesh K. Agarwala ◽  
Noshir A. Langrana ◽  
Stephen C. Danforth

Abstract Fused Deposition of Ceramics (FDC) is a Solid Freeform Fabrication (SFF) technique under development at Rutgers University. This technique is based on Fused Deposition Modeling (FDM)2, a commercially available SFF technology. Freeform fabrication of ceramic and metal parts is a means of significantly lowering the cost of currently expensive components. The feasibility of Fused Deposition of Ceramics (FDC) has been demonstrated in the recent past. Crucial to the viable fabrication of ceramic components is the elimination of defects in the parts. Apart from some of the usual traits of SFF techniques, some distinct features of FD Processing lead to defects in fabricated parts. The focus of this work is to study and improve the build procedure of FDM, thereby reducing the defects that are associated with FD processing. Predictable errors in the FDC/FDM components need to be consistently eliminated to increase the yield of fully dense, defect free, green parts. Changes in the manufacturing procedure and operation of FDC are shown to reduce these errors. Fully dense green components are further processed to obtain defect free fully dense sintered ceramic parts.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Wiktoria Maria Wojnarowska ◽  
Jakub Najowicz ◽  
Tomasz Piecuch ◽  
Michał Sochacki ◽  
Dawid Pijanka ◽  
...  

Purpose Chicken orthoses that cover the ankle joint area are not commercially available. Therefore, the main purpose of this study is to fabricate a customised temporary Ankle–Foot Orthosis (AFO) for a chicken with a twisted ankle using computer-aided design (CAD) and three-dimensional (3D) printing. The secondary objective of the paper is to present the specific application of Additive Manufacturing (AM) in veterinary medicine. Design/methodology/approach The design process was based on multiple sketches, photos and measurements that were provided by the owner of the animal. The 3D model of the orthosis was made with Autodesk Fusion 360, while the prototype was fabricated using fused deposition modelling (FDM). Evaluation of the AFO was performed using the finite element method. Findings The work resulted in a functional 3D printed AFO for chicken. It was found that the orthosis made with AM provides satisfactory stiffen and a good fit. It was concluded that AM is suitable for custom bird AFO fabrication and, in some respects, is superior to traditional manufacturing methods. It was also concluded that the presented procedure can be applied in other veterinary cases and to other animal species and other parts of their body. AM provides veterinary with a powerful tool for the production of well-fitted and durable orthoses for animals. Research limitations/implications The study does not include the chicken's opinion on the comfort or fit of the manufactured AFO due to communication issues. Evaluation of the final prototype was done by the researchers and the animal owner. Originality/value No evidence was found in the literature on the use of AM for chicken orthosis, so this study is the first to describe such an application of AM. In addition, the study demonstrates the value of AM in veterinary medicine, especially in the production of devices such as orthoses.


2020 ◽  
Vol 1 (2) ◽  
pp. 81-91
Author(s):  
Frince Marbun ◽  
Richard A.M. Napitupulu

3D printing technology has great potential in today's manufacturing world, one of its uses is in making miniatures or prototypes of a product such as a piston. One of the most famous and inexpensive 3D printing (additive manufacturing) technologies is Fused Deposition Modeling (FDM), the principle FDM works by thermoplastic extrusion through a hot nozzle at melting temperature then the product is made layer by layer. The two most commonly used materials are ABS and PLA so it is very important to know the accuracy of product dimensions. FDM 3D Printing Technology is able to make duplicate products accurately using PLA material. FDM machines work by printing parts that have been designed by computer-aided design (CAD) and then exported in the form of STL or .stl files and uploaded to the slicer program to govern the printing press according to the design. Using Anet A8 brand 3D printing tools that are available to the public, Slicing of general CAD geometry files such as autocad and solidwork is the basis for making this object. This software is very important to facilitate the design process to be printed. Some examples of software that can be downloaded and used free of charge such as Repetier-Host and Cura. by changing the parameters in the slicer software is very influential in the 3D printing manufacturing process.


Author(s):  
James I. Novak ◽  
Mark Zer-Ern Liu ◽  
Jennifer Loy

This chapter builds new knowledge for design engineers adopting fused deposition modeling (FDM) technology as an end manufacturing process, rather than simply as a prototyping process. Based on research into 2.5D printing and its use in real-world additive manufacturing situations, a study featuring 111 test pieces across the range of 0.4-4.0mm in thickness were analyzed in increments of 0.1mm to understand how these attributes affect the quality and print time of the parts and isolate specific dimensions which are optimized for the FDM process. The results revealed optimized zones where the outer wall, inner wall/s, and/or infill are produced as continuous extrusions significantly faster to print than thicknesses falling outside of optimized zones. As a result, a quick reference graph and several equations are presented based on fundamental FDM principles, allowing design engineers to implement optimized wall dimensions in computer-aided design (CAD) rather than leaving print optimization to technicians and manufacturers in the final process parameters.


1999 ◽  
Author(s):  
Merve Erdal ◽  
Levent Ertoz ◽  
Selçuk Güçeri

Abstract Fused deposition based solid freeform fabrication technique allows manufacturing of potential functional preforms for subsequent Resin Transfer Molding. In this study, the transport property (permeability) of solid freeform fabricated porous preform geometries are investigated. Specifically the effect of pore geometry and network on the permeability is sought. Wet (saturated) permeability experiments were performed for various pore geometries with different viscosity liquids. For all fluids and preform structures investigated in this study, the porous flow exhibited Darcian behavior. The permeability is affected by changes in order of magnitude of fluid viscosity, the effect considerably significant in low porosity preforms. Current work concentrates on dry permeability measurement and development of numerical permeability models for ordered pore geometries (as produced through SFF) that will be compared with experimental results.


2010 ◽  
Vol 4 (4) ◽  
Author(s):  
Ibrahim T. Ozbolat ◽  
Bahattin Koc

This paper presents a computer-aided design (CAD) of 3D porous tissue scaffolds with spatial control of encapsulated biomolecule distributions. A localized control of encapsulated biomolecule distribution over 3D structures is proposed to control release kinetics spatially for tissue engineering and drug release. Imaging techniques are applied to explore distribution of microspheres over porous structures. Using microspheres in this study represents a framework for modeling the distribution characteristics of encapsulated proteins, growth factors, cells, and drugs. A quantification study is then performed to assure microsphere variation over various structures under imaging analysis. The obtained distribution characteristics are mimicked by the developed stochastic modeling study of microsphere distribution over 3D engineered freeform structures. Based on the stochastic approach, 3D porous structures are modeled and designed in CAD. Modeling of microsphere and encapsulating biomaterial distribution in this work helps develop comprehensive modeling of biomolecule release kinetics for further research. A novel multichamber single nozzle solid freeform fabrication technique is utilized to fabricate sample structures. The presented methods are implemented and illustrative examples are presented in this paper.


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