Thermo-Geometrical Design Models for Solid Freeform Fabrication With Material Transfer

1998 ◽  
Author(s):  
Charalabos Doumanidis ◽  
Yong-Min Kwak
Keyword(s):  
Fused Deposition Modeling ◽  
Solid Freeform Fabrication ◽  
Heat Transfer Analysis ◽  
Material Structure ◽  
Process Conditions ◽  
Transfer Model ◽  
Material Transfer ◽  
Surface Geometry ◽  
Freeform Fabrication ◽  
Fused Deposition

Abstract In thermal solid freeform fabrication of layered products, simultaneous quality assurance of the part geometry and material structure requires concurrent design of the process conditions with the product features. For a heat transfer analysis yielding the material structure, an analytical, distributed-parameter quasi-linear thermal model is developed and tested in scan welding. This is based on Green’s field, identified in-process by infrared temperature sensing to reflect thermal nonlinearities. Similarly, a mass transfer model of the layer surface geometry is established on an analogous concept of the material deposition field, approximated by an ellipsoidal shape and identified in-process by Laser 3D scanning of the part topology in fused deposition modeling tests. The invertibility and computational efficiency of both models provide a basis for design of adaptive feedback control strategies for the thermogeometrical characteristics of rapid prototypes.

scholarly journals Main 3D Manufacturing Techniques for Customized Bone Substitutes. A Systematic Review

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2524
Author(s):  
Javier Montero ◽  
Alicia Becerro ◽  
Beatriz Pardal-Peláez ◽  
Norberto Quispe-López ◽  
Juan-Francisco Blanco ◽  
...  
Keyword(s):  
Bone Regeneration ◽  
Fused Deposition Modeling ◽  
Solid Freeform Fabrication ◽  
Bone Substitutes ◽  
Cochrane Library ◽  
3D Scaffold ◽  
Hand Search ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Bone Scaffolds

Clinicians should be aware of the main methods and materials to face the challenge of bone shortage by manufacturing customized grafts, in order to repair defects. This study aims to carry out a bibliographic review of the existing methods to manufacture customized bone scaffolds through 3D technology and to identify their current situation based on the published papers. A literature search was carried out using “3D scaffold”, “bone regeneration”, “robocasting” and “3D printing” as descriptors. This search strategy was performed on PubMed (MEDLINE), Scopus and Cochrane Library, but also by hand search in relevant journals and throughout the selected papers. All the papers focusing on techniques for manufacturing customized bone scaffolds were reviewed. The 62 articles identified described 14 techniques (4 subtraction + 10 addition techniques). Scaffold fabrication techniques can be also be classified according to the time at which they are developed, into Conventional techniques and Solid Freeform Fabrication techniques. The conventional techniques are unable to control the architecture of the pore and the pore interconnection. However, current Solid Freeform Fabrication techniques allow individualizing and generating complex geometries of porosity. To conclude, currently SLA (Stereolithography), Robocasting and FDM (Fused deposition modeling) are promising options in customized bone regeneration.

Process Improvements in Fused Deposition of Ceramics (FDC): Progress Towards Structurally Sound Components

1996 ◽  
Author(s):  
Vikram R. Jamalabad ◽  
Mukesh K. Agarwala ◽  
Noshir A. Langrana ◽  
Stephen C. Danforth
Keyword(s):  
Fused Deposition Modeling ◽  
Solid Freeform Fabrication ◽  
Sintered Ceramic ◽  
Process Improvements ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Ceramic Components ◽  
Manufacturing Procedure ◽  
Fused Deposition Of Ceramics ◽  
The Cost

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.

Distributed-Parameter Modeling for Geometry Control of Manufacturing Processes With Material Deposition

1998 ◽  
Vol 122 (1) ◽  
pp. 71-77 ◽  
Author(s):  
Charalabos Doumanidis ◽  
Eleni Skordeli
Keyword(s):  
Solid Freeform Fabrication ◽  
Surface Topology ◽  
Distributed Parameter ◽  
Surface Geometry ◽  
Mass Source ◽  
Freeform Fabrication ◽  
Geometry Model ◽  
Material Deposition ◽  
Solid Objects ◽  
3D Solid

Recent solid freeform fabrication methods generate 3D solid objects by material deposition in successive layers made of adjacent beads. Besides numerical simulation, this article introduces an analytical model of such material addition, using superposition of unit deposition distributions, composed of elementary spherical primitives consistent with the mass transfer physics. This real-time surface geometry model, with its parameters identified by in-process profile measurements, is used for Smith-prediction of the material shape in the unobservable deposition region. The model offers the basis for a distributed-parameter geometry control scheme to obtain a desired surface topology, by modulating the feed and motion of a moving mass source. The model was experimentally tested on a fused wire deposition welding station, using optical sensing by a scanning laser stripe. Its applications to other rapid prototyping methods are discussed. [S0022-0434(00)02301-7]

Characterization of Permeability for Solid Freeform Fabricated Porous Structures

1999 ◽  
Author(s):  
Merve Erdal ◽  
Levent Ertoz ◽  
Selçuk Güçeri
Keyword(s):  
Solid Freeform Fabrication ◽  
Pore Geometry ◽  
Fluid Viscosity ◽  
Porous Structures ◽  
Permeability Measurement ◽  
Porous Flow ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Order Of Magnitude

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.

Solid Freeform Fabrication of Silicon Nitride Ceramics

1998 ◽  
Vol 542 ◽  
Author(s):  
C. J. Gasdaska ◽  
R. Clancy ◽  
V. Jamalabad ◽  
D. Dalfonzo
Keyword(s):  
Thermal Expansion ◽  
Silicon Nitride ◽  
Solid Freeform Fabrication ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Thermal Expansion Coefficients ◽  
Processed Material ◽  
Nitride Ceramics ◽  
Internal Cavities ◽  
Expansion Coefficients

AbstractSilicon nitride ceramics have been prepared using the fused deposition (FD) process in a Stratasys 1650 modeler. Two types of silicon nitride have been prepared: GS44 and AS800. AS800 is processed and used at higher temperatures than GS44. The strength of machined surfaces of either type of silicon nitride prepared using FD is comparable to conventionally processed material. Using standard build conditions strengths for as-built and as-sintered surfaces are approximately 50% lower. The additive nature of solid freeform processes also allows multi-material combinations to be deposited which result in enhanced performance. For example, combinations of silicon nitride based materials with different thermal expansion coefficients have been prepared which demonstrate strength increases > 20%. In addition, components containing complicated internal cavities may also be fabricated.

Design of Fused-Deposition ABS Components for Stiffness and Strength

2000 ◽  
Author(s):  
José F. Rodríguez ◽  
James P. Thomas ◽  
John E. Renaud
Keyword(s):  
Mechanical Performance ◽  
Solid Freeform Fabrication ◽  
Acrylonitrile Butadiene Styrene ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Load Carrying ◽  
Volume Production ◽  
Approximate Minimization ◽  
High Degree ◽  
Functional Components

Abstract The high degree of automation of Solid Freeform Fabrication (SFF) processing and its ability to create geometrically complex parts to precise dimensions provide it with a unique potential for low volume production of rapid tooling and functional components. A factor of significant importance in the above applications is the capability of producing components with adequate mechanical performance (e.g., stiffness and strength). This paper introduces a strategy for the optimizing the design of Fused-Deposition Acrylonitrile-Butadiene-Styrene (FD-ABS) components for stiffness and strength. In this strategy, a mathematical model of the structural system is linked to an approximate minimization algorithm to find the settings of select manufacturing parameters which optimize the mechanical performance of the component. The methodology is demonstrated by maximizing the load carrying capacity of a two-section cantilevered FD-ABS beam.

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 ◽  
...  
Keyword(s):  
Computer Aided Design ◽  
Composite Structures ◽  
Volume Fraction ◽  
Solid Freeform Fabrication ◽  
Side Lobe ◽  
Electromechanical Properties ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Fused Deposition Of Ceramics ◽  
Aided Design

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.

Testing of the ABS Materials for Application in Fused Deposition Modeling Technology

2013 ◽  
Vol 309 ◽  
pp. 133-140 ◽  
Author(s):  
Ludmila Novakova-Marcincinova ◽  
Jozef Novak-Marcincin
Keyword(s):  
Rapid Prototyping ◽  
Lead Zirconate Titanate ◽  
Fused Deposition Modeling ◽  
Acrylonitrile Butadiene Styrene ◽  
Lead Zirconate ◽  
Material Structure ◽  
Fused Deposition Modelling ◽  
Initial State ◽  
Fused Deposition ◽  
Materials Used

In paper are presented knowledge about types and properties of materials used for production of models using by rapid prototyping Fused Deposition Modelling (FDM) method. In today used rapid prototyping technologies is used material in initial state as solid, liquid or powder material structure. In solid state are used various forms such as pellets, wire or laminates. Basic range materials include paper, nylon, wax, resins, metals and ceramics. In FDM rapid prototyping technology are mainly used as basic materials ABS (Acrylonitrile Butadiene Styrene), polyamide, polycarbonate, polyethylene and polypropylene. For advanced FDM applications are used special materials as silicon nitrate, PZT (Piezoceramic Material - Lead Zirconate Titanate), aluminium oxide, hydroxypatite and stainless steel.

Design of Fused-Deposition ABS Components for Stiffness and Strength

2003 ◽  
Vol 125 (3) ◽  
pp. 545-551 ◽  
Author(s):  
Jose´ F. Rodrı´guez ◽  
James P. Thomas ◽  
John E. Renaud
Keyword(s):  
Mechanical Performance ◽  
Solid Freeform Fabrication ◽  
Acrylonitrile Butadiene Styrene ◽  
Freeform Fabrication ◽  
Fused Deposition ◽  
Load Carrying ◽  
Volume Production ◽  
Approximate Minimization ◽  
High Degree ◽  
Functional Components

The high degree of automation of Solid Freeform Fabrication (SFF) processing and its ability to create geometrically complex parts to precise dimensions provide it with a unique potential for low volume production of rapid tooling and functional components. A factor of significant importance in the above applications is the capability of producing components with adequate mechanical performance (e.g., stiffness and strength). This paper introduces a strategy for optimizing the design of Fused-Deposition Acrylonitrile-Butadiene-Styrene (FD-ABS; P400) components for stiffness and strength under a given set of loading conditions. In this strategy, a mathematical model of the structural system is linked to an approximate minimization algorithm to find the settings of select manufacturing parameters, which optimize the mechanical performance of the component. The methodology is demonstrated by maximizing the load carrying capacity of a two-section cantilevered FD-ABS beam.

Research on Curved Layer Fused Deposition Modeling (CLFDM) With Variable Extruded Filament (VEF)

2018 ◽  
Author(s):  
Donghua Zhao ◽  
Weizhong Guo
Keyword(s):  
Additive Manufacturing ◽  
Fused Deposition Modeling ◽  
Solid Freeform Fabrication ◽  
Low Cost ◽  
Theoretical Point ◽  
Fundamental Study ◽  
Strength Performance ◽  
Longitudinal Tensile Strength ◽  
Fused Deposition ◽  
Deposition Modeling

Fused Deposition Modeling (FDM), an Additive Manufacturing (AM) technique, is widely used due to its low-cost and open source. Geometry accuracy and strength performance of the printed parts are closely related to inter-layer bonding between adjacent layers and inter-road bonding in the layer. Because of the limit of layer-based AM, the longitudinal tensile strength of the filaments is much higher than the bonding strength between adjacent filaments, which brings anisotropy of the printed part. While CLFDM is devoted to solve this problem and obtain better geometry accuracy and meanwhile decrease build time by virtue of high continuity of filament, reduced stair-step effect, and lesser number of layers, especially when manufacturing thin and curved parts (shells). However, to the best of our knowledge in the aspects of process modeling of CLFDM, available researches focus mainly on simple curved layer, instead of more intricate ones possessing tiny features, which are more common in manufacturing. Therefore, to realize Solid Freeform Fabrication (SFF), this paper researches CLFDM with VEF (simultaneously changing the direction and the dimension of extruded filament according to manufacturing demand of the curved layer), which would be a fundamental study and a foundation for Advanced Design for Additive Manufacturing (ADFAM), slicing and path planning (extruder path generation) in 3D space. To realize slicing and printing with homogeneous and inhomogeneous extruded filament between consecutive layers and within the layer (flat or curved), models of flat layer FDM and CLFDM with VEF are respectively established. Then, the relationships among key process parameters are analyzed. Finally, graphical simulation of the proposed strategy based on a vase is provided to verify its effectiveness and advantages from a theoretical point of view. In general, variable direction of extruded filament along tangential directions of part surface imparts smoother surfaces, instead of rough exterior appearance resulting from stair-step effects. And variable dimension of extruded filament maximizes material extruded to increase build speed wherever allowed and minimizes deposition size for resolution whenever needed, resulting in curved layer surfaces with uneven layer thickness and having tiny features.

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