Soft Tooling-Friendly Inductive Mold Heating—A Novel Concept

In order to economize injection molded prototypes, additive manufacturing of, e.g., curable plastics based tools, can be employed, which is known as soft tooling. However, one disadvantage of such tools is that the variothermal process, which is needed to produce polymeric parts with small features, can lead to a shorter lifespan of the tooling due to its thermally impaired material properties. Here, a novel concept is proposed, which allows to locally heat the mold cavity via induction to circumvent the thermal impairment of the tooling material. The developed fabrication process consists of additive manufacturing of the tooling, PVD coating the mold cavity with an adhesion promoting layer and a seed layer, electroplating of a ferromagnetic metal layer, and finally patterning the metal layer via laser ablation to enhance the quality and efficiency of the energy transfer as well as the longevity by geometric measures. This process chain is investigated on 2D test specimens to find suitable fabrication parameters, backed by adhesion tests as well as environmental and induction tests. The results of these investigations serve as proof of concept and form the base for the investigation of such induction layers in actual soft tooling cavities.

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Preventing and Detecting Cyber Attacks (Stl & Amf) on Additive Manufacturing (Am) Process Chain

SSRN Electronic Journal ◽

10.2139/ssrn.3492693 ◽

2018 ◽

Author(s):

Anil Lamba ◽

Satinderjeet Singh ◽

Balvinder Singh ◽

Natasha Dutta ◽

Sivakumar Sai Rela Muni

Keyword(s):

Additive Manufacturing ◽

Cyber Attacks ◽

Process Chain

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Design of Shape Memory Thermoplastic Material Systems for FDM-Type Additive Manufacturing

Materials ◽

10.3390/ma14154254 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4254

Author(s):

Paulina A. Quiñonez ◽

Leticia Ugarte-Sanchez ◽

Diego Bermudez ◽

Paulina Chinolla ◽

Rhyan Dueck ◽

...

Keyword(s):

Additive Manufacturing ◽

Shape Memory ◽

Thermomechanical Processing ◽

Material Selection ◽

Shape Memory Polymer ◽

Fused Filament Fabrication ◽

Materials Development ◽

Thermoplastic Material ◽

Polymer Systems ◽

Injection Molded

The work presented here describes a paradigm for the design of materials for additive manufacturing platforms based on taking advantage of unique physical properties imparted upon the material by the fabrication process. We sought to further investigate past work with binary shape memory polymer blends, which indicated that phase texturization caused by the fused filament fabrication (FFF) process enhanced shape memory properties. In this work, two multi-constituent shape memory polymer systems were developed where the miscibility parameter was the guide in material selection. A comparison with injection molded specimens was also carried out to further investigate the ability of the FFF process to enable enhanced shape memory characteristics as compared to other manufacturing methods. It was found that blend combinations with more closely matching miscibility parameters were more apt at yielding reliable shape memory polymer systems. However, when miscibility parameters differed, a pathway towards the creation of shape memory polymer systems capable of maintaining more than one temporary shape at a time was potentially realized. Additional aspects related to impact modifying of rigid thermoplastics as well as thermomechanical processing on induced crystallinity are also explored. Overall, this work serves as another example in the advancement of additive manufacturing via materials development.

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Closing the Loop - Recycling Plastic Waste

10.26686/wgtn.17145728.v1 ◽

2021 ◽

Author(s):

◽

Caitlin Bruce

Keyword(s):

New Zealand ◽

Additive Manufacturing ◽

Circular Economy ◽

Building Material ◽

New Technologies ◽

Plastic Waste ◽

Proof Of Concept ◽

Waste Production ◽

Closing The Loop ◽

3D Printed

<p>New Zealand is ranked among the top nations in waste production, including a million tonnes of plastic waste. Currently, there are methods for recycling plastic within New Zealand but these methods can be expensive and time-consuming, resulting in most of the plastic being thrown into the landfill. Because plastic does not fully degrade, it ends up in the ocean and other waterways, poisoning the water with toxins. The purpose of this research is to provide a solution to reducing plastic waste by creating an alternative method of recycling that utilises new technologies such as additive manufacturing, to create a building material that fits into the concept of the circular economy. The findings of this research explored the recycling of plastic by collecting plastic waste such as PLA (Polylactic Acid) from old 3D printed models. The plastic was recycled into filament for additive manufacturing (AM) and used to print building tile, establishing an initial proof of concept for the use of recycled plastic as a potential building material.</p>

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Адитивне формування вуглекомпозитів на основі L-полілактиду

Bulletin of the Kyiv National University of Technologies and Design Technical Science Series ◽

10.30857/1813-6796.2019.6.10 ◽

2020 ◽

Vol 140 (6) ◽

pp. 104-111

Author(s):

Р. Ш. Іскандаров ◽

Н. В. Сова ◽

Б. М. Савченко ◽

І. І. П'ятничук ◽

В. А. Татаренко

Keyword(s):

Tensile Strength ◽

Additive Manufacturing ◽

Carbon Fiber ◽

Carbon Fibers ◽

Polymer Matrix ◽

Fiber Composites ◽

Carbon Composite ◽

Test Method ◽

Carbon Fiber Composites ◽

Injection Molded

Study of the FFF additive manufacturing process of composite material based on L – polylactide (PLLA) with ultra-short carbon fibers. Tensile strength and elongation at break for all test specimens were determined according to ISO 527. Tensile modulus - ASTM D638-10, specimen density - PN-EN ISO 1183, microscopic examination - according to ASTM E2015 - 04 (2014). Charpy Shock Tests ISO 179 and ASTM D256. Bending test method ISO 178 and ASTM D 790. The rational modes of FFF additive manufacturing (AM) of carbon fiber composite based on PLLA was established. Properties of carbon fiber PLLA and unfilled PLLA was determinated for AM formed samples and injection molded samples. Carbon fiber composites have significantly higher flexural and tensile module us values compared to the original L-polylactide, which is due to the effect of polymer matrix reinforcement by the fibrous component. However, finished products obtained by AM PLLA carbon composite have a lower impact strength and tensile strength, which is likely to be due to the fact that the carbon fibers are short (50-60 mkm) and have a cavitations effect during injection molding and AM. Density of carbon fiber filled PLLLA was lower the theoretically calculated value for filament material as well for injection molded and AM formed samples. Density reduction probably the main cause of impact properties deterioration due to cavity forming around carbon fibers. Density and tensile properties of AM formed samples can be changed by AM slicing parameter – extrusion multiplier. Cavitation effect for carbon fiber composites observed for PLLA composite in form AM filament, injection molded parts and AM formed samples. Cavity forming was confirmed by optical microscopy and density measurement. Possible reason for cavity forming is orientation deformation of the fiber in polymer matrix during the formation of the filament. The effect of cavitation also persists in the AM of products from carbon composites due to the passage of the orientation at the exit of the printer nozzle. The possibility of regulating the density and physical and mechanical properties of carbon composite products obtained by the additive manufacturing method has been established. Selection of rational values of the extrusion multiplier and the direction of the layers in the additive molding allows you to create products with the desired complex of properties.

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Energy Efficient Multi-Robotic 3D Printing for Large-Scale Construction – Framework, Challenges, and a Systematic Approach

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2021-63787 ◽

2021 ◽

Author(s):

Azadeh Haghighi ◽

Abdullah Mohammed ◽

Lihui Wang

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Energy Efficient ◽

Large Scale ◽

Systematic Approach ◽

Smart Manufacturing ◽

Energy Aware ◽

Robot Positioning ◽

Novel Concept ◽

And Control

Abstract An emerging trend in smart manufacturing of the future is robotic additive manufacturing or 3D printing which introduces numerous advantages towards fast and efficient printing of high-quality customized products. In the case of the construction industry, and specifically in large-scale settings, multi-robotic additive manufacturing (i.e., adopting a team of 3D printer robots) has been found to be a promising solution in order to overcome the existing size limitations. Consequently, several research efforts regarding the development and control of such robotic additive manufacturing solutions have been reported in the literature. However, given the increasing environmental concerns, establishing novel methodologies for energy-efficient processing and planning of these systems towards higher sustainability is necessary. This paper presents a novel framework towards energy-efficient multi-robotic additive manufacturing and describes the overall challenges with respect to the energy efficiency. The energy module of the proposed framework is implemented in a simulation environment. In addition, a systematic approach for energy-aware robot positioning is introduced based on the novel concept of reciprocal energy map. The reciprocal energy map is established based on the original energy map calculated by the energy module and can be used for identifying the low energy zones for positioning and relocation of robots during the printing process.

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Strukturoptimierte Zerspanungswerkzeuge*/Structure-optimized cutting tools – CAE process chain for designing additively manufactured tool bodies

wt Werkstattstechnik online ◽

10.37544/1436-4980-2018-06-61 ◽

2018 ◽

Vol 108 (06) ◽

pp. 435-440

Author(s):

E. Abele ◽

T. Scherer ◽

E. Schmidt

Keyword(s):

Additive Manufacturing ◽

Cutting Tools ◽

Scientific Research ◽

Wird Eine ◽

Process Chain ◽

Additive Fertigung ◽

Additive Processes ◽

Finite Elemente ◽

Complex Components

Die additive Fertigung von Zerspanungswerkzeugen rückt stärker in den Fokus industrieller und wissenschaftlicher Forschungsarbeiten. Die Designfreiheit additiver Verfahren ermöglicht die Herstellung komplexer Bauteile mit materialeffizienter und kraftflussgerechter Geometrie. Um diese Potenziale für neuartige Werkzeugkonzepte zu nutzen, wird eine CAE-Prozesskette zur Durchführung einer Finite-Elemente-Analyse (FEA) und anschließender Strukturoptimierung, basierend auf am Markt verfügbaren Softwarelösungen, vorgestellt.   Additive manufacturing of cutting tools is becoming more and more the focus of industrial and scientific research. The freedom of design of additive processes enables the production of complex components with material-efficient and force flux oriented geometry. To exploit this potential for novel tool concepts, a CAE process chain is presented for implementing an FEA and subsequently optimizing the structure based on software solutions available on the market.

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Hybride Fertigung mittels Laser-Strahlschmelzen/Hybrid manufacturing by laser-based powder bed fusion

wt Werkstattstechnik online ◽

10.37544/1436-4980-2021-06-7 ◽

2021 ◽

Vol 111 (06) ◽

pp. 363-367

Author(s):

Lukas Langer ◽

Matthias Schmitt ◽

Georg Schlick ◽

Johannes Schilp

Keyword(s):

Additive Manufacturing ◽

Manufacturing Processes ◽

Complex Geometries ◽

Hybrid Manufacturing ◽

Powder Bed Fusion ◽

Process Chain ◽

Manufacturing Costs ◽

Additive Fertigung ◽

Powder Bed

Die additive Fertigung ermöglicht komplexe Geometrien und individualisierte Bauteile. Die hohen Material- und Fertigungskosten können ein Hindernis für einen wirtschaftlichen Einsatz sein. In der hybriden additiven Fertigung werden die Vorteile konventioneller sowie additiver Fertigungsverfahren kombiniert. Für eine weitere Steigerung der Wirtschaftlichkeit und Effizienz werden nichtwertschöpfende Schritte der Prozesskette identifiziert und Automatisierungsansätze entwickelt.   Additive manufacturing enables complex geometries and individualized components. However, high material and manufacturing costs can be a hindrance for economical use. Hybrid additive manufacturing combines the advantages of conventional with additive manufacturing processes. For a further increase in profitability and efficiency, non-value-adding steps in the process chain are identified and automation approaches developed.

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