News

ITMA 2023 in Milan

The research area presents itself at the world's largest international exhibition for textile and clothing technology in Milan.

Research Area Technical Textiles and Hof University at ITMA Anne Böhm from Hof University, ifm left and Silke Grosch from Fraunhofer right
Booth of Fraunhofer ITWM at ITMA 2023

At ITMA 2023 The Fraunhofer Textile Research Unit presented itself with and at the stand of Hof University of Applied Sciences from June 8 to 14 of this year. Under the motto "Transforming the World", the main focus was on the topic of sustainability, which will significantly determine the future of the textile world. Many contacts were made. We received inquiries especially on the topics of sustainability and smart textiles.

Here to the trade fair review: ITMA 2023 Ends on a High Note

The Fraunhofer ITWM presented itself at its own booth and mainly served its customers in the nonwovens sector. Information about the successful cooperation with the companies Siriotek and bematic can be found here --> 2023_05_31_ITMA - Fraunhofer ITWM.

JEC 2023

From April 25 - 27, the Fraunhofer Institutes IWU, IAP, ITWM and ISC participated in the world's leading composites trade fair JEC in Paris.

© Fraunhofer ISC
Fraunhofer ISC and Hof University

The picture shows the team of Fraunhofer ISC-HTL, Eva Paulack and Dr. Jens Schmidt, who presented the R&D work at the Textile Campus Münchberg together with the staff of Hof University of Applied Sciences, Alexandra Luft and Professor Claus-Ekkehard Koukal. With more than 30 new contacts, among others to international companies and institutes, the fair was very successful for the cooperation partners.

Sustainable natural-fiber reinforcement for textile-reinforced concrete components

Textile-reinforced concrete components with a sustainable natural-fiber reinforcement possess sufficient bond and tensile load-bearing behavior for the utilization in construction. This has been verified by researchers at the Fraunhofer WKI in collaboration with Biberach University of Applied Sciences and the industrial partner FABRINO. In the future, textile-reinforced components with natural-fiber reinforcement could therefore replace conventionally reinforced concrete components and improve the environmental balance in the construction industry.

© Fraunhofer WKI
At the Fraunhofer WKI, researchers have developed a flax leno fabric with a bio-based coating as the foundation for a natural-fiber reinforcement.
© Fraunhofer WKI
The renewable natural fibers used for the leno fabric - which are available regionally or Europe-wide - and a partially bio-based coating contribute towards improving the carbon footprint of the construction industry.

Non-metallic reinforcements for concrete elements are currently often made from various synthetically produced fibers - for example from glass or carbon fibers. An ecological alternative to synthetic fibers is provided by flax or other natural fibers. These are widely available and are more sustainable, due, amongst other things, to their renewable raw-material basis, the advantages regarding recycling, and the lower energy requirements during production. This is where the researchers from the Fraunhofer WKI and Biberach University of Applied Sciences, in collaboration with an industrial partner, became active. Their goal was to demonstrate that reinforcements made from textile fibers are just as suitable for utilization in construction as synthetic fibers.

"At the Fraunhofer WKI, we have produced leno fabrics from flax-fiber yarn using a weaving machine. In order to enhance sustainability, we tested a treatment of the flax yarns for improving the tensile strength, durability and adhesion which is ecologically advantageous compared to petro-based treatments," explained Jana Winkelmann, Project Manager at the Fraunhofer WKI. In the coating process, a commonly used petro-based epoxy resin was successfully replaced by a partially bio-based impregnation. A large proportion (56%) of the molecular structure of the utilized epoxy resin consists of hydrocarbons of plant origin and can therefore improve the CO2 balance.

Textile reinforcements have a number of fundamental advantages. They exhibit, for example, significantly reduced corrodibility at the same or higher tensile strength than steel, with the result that the necessary nominal dimension of the concrete covering can be reduced. This often allows smaller cross-sections to be required for the same load-bearing capacity. Up to now, however, the load-bearing behavior of textile reinforcements made from natural fibers in concrete components has not been systematically investigated.

At Biberach University of Applied Sciences, researchers tested the bond and tensile load-bearing behavior as well as the uniaxial flexural load-bearing behavior of concrete components with textile reinforcement made from flax fibers. The scientists came to the conclusion that the natural-fiber-based textile-reinforced components with a bio-based impregnation are fundamentally suitable. The suitability was demonstrated by both a significant increase in the breaking load compared to non-reinforced and under-reinforced concrete components and in finely distributed crack patterns. The curves of the stress-strain diagrams could be divided into three ranges typical for reinforced expansion elements (State I - non-cracked, State IIa - initial cracking, and State IIb - final crack pattern). The delineation of the ranges becomes more pronounced as the degree of reinforcement increases.

As a whole, regionally or Europe-wide available, renewable natural fibers and a partially bio-based coating contribute towards an improvement of the CO2 footprint of the construction industry. As a result, a further opportunity is being opened up for the energy- and raw-material-intensive construction industry in terms of meeting increasingly stringent environmental and sustainability requirements. "Textile-reinforced concretes enable lighter and more slender structures and therefore offer architectural leeway. We would like to continue our research into the numerous application possibilities of natural-fiber-reinforced concretes," said Christina Haxter, a staff member at the Fraunhofer WKI.

Last modified:  March 15, 2023

Funding

The project, which ran from 9th December 2020 to 31st December 2022, was funded by the German Federal Environmental Foundation (DBU). 

Techtextil 2022

Featuring more than 100 customer meetings, this year's Techtextil was very successful with its re-launch in new halls for the Technical Textile Research Area at booth 12.0 D15. The international trade fair took place under the motto "Beyond Innovation" together with Texprocess and the once-only Heimtextil Summer Special.

© ©Fraunhofer Textil
© ©Fraunhofer Textil

The eye-catcher of the Fraunhofer booth was the e-Textiles dress from the Second Skins project, developed by FashionTech expert Malou Beemer together with Fraunhofer IZM. Sensors and actuators for use in PPE, medical technology and lightweight construction were demonstrated, as were sustainable flax-based organosheets and innovative scPLA fiber-based monomaterial composites through to near-net-shape preforms for ceramic composites CMC for the high-temperature range. With its additively printed headset, Fraunhofer IWU illustrated its expertise in equipment development for the most sophisticated additive printing processes (SEAM) and the latest state of TowPreg process. Last but not least to mention the competences in process and product simulation of Fraunhofer ITWM, which again attracted great interest.

We thank our customers and business partners for the interest in our news. A selection of the developments of the Fraunhofer research area can be found in the following news.

Innvoations at Techtextil 2022: Modular Hardware Kit and Contact Technologies for e-Textiles

IZM developed an Arduino-based modular hardware platform that allows e-textile prototypes and small series to be integrated into textiles in an easier, more flexible and more reliable way. Modules already available include various sensors (temperature, proximity, pulse, IMU) as well as actuators, RGB LEDs, ADC, µC, Bluetooth and more. In addition to the conventional sewing of the modules using electrically conductive yarn, all modules also offer the possibility of integrating them mechanically and electrically in a one-step process using the proprietary e-Textile Bond technology developed at IZM.

© © Malou Beemer & Patrick Klein Meuleman
© © Malou Beemer & Patrick Klein Meuleman

The project

As part of the European STARTS project Re-FREAM, designers, technologists and scientists conducted joint research on future as well as sustainable technologies for the textile industry. In the e-Textiles research area, fashion tech expert Malou Beemer from the Netherlands worked with an international team including IZM on adaptive garments that can adapt to users' practical and social needs. In this project Second Skins, hardware modules developed by IZM are used. Here, for example, Smart IMU modules capture the wearer's body language and movement data, and proximity sensors are also integrated. The sensor data obtained can be used to control individual lighting effects of the RGB-LED display, through which the wearer communicates non-verbally with her environment. All modules can be freely placed on the garment during the design process. For power supply and communication with the process unit, a textile 4-wire IIC bus conductor made of a thermoplastic insulated hybrid conductor of stranded material and reinforcing textile fibers is embroidered onto the undergarment, thus connecting the modules. The electrical connection between the module and the textile bus is then made using the aforementioned e-Textile Bonding technology, which provides reliable but also repairable contacting without the need for additional additives such as pastes, fluxes or the like. Due to the remeltability of the thermoplastic adhesive, the module can also be thermally removed from the carrier again. The inner layer between the upper and lower garment contains thin textile layers that allow masking of the lighting effects by means of 3-D printing or lamination, thus allowing the user to customize the lighting design.

Links: https://www.maloubeemer.com/project/second-skins-re-fream/  und https://re-fream.eu/pioneers/second-skins/

Contact:

Fraunhofer-Institut für Zuverlässigkeit und Mikrointegration IZM

Malte von Krshiwoblozki # 

Fraunhofer IZM Smart Textiles

One software for all cases – simulating technical textiles realistically

"TexMath" The software tool for technical textiles as well as nonwovens

Simulated spacer fabric
© @ITWM
Tensions in a textil mask
© @ITWM

athematics at #Techtextil? Of course, because mathematics flows in almost everywhere. A team from the "Flow and Material Simulation" department of @FraunhoferITWM will be on site at the fair to present the #softwaretool "TexMath", which helps to analyze, understand and optimize technical textiles as well as nonwovens made of #plastic or #natural fibers. The tool improves both virtual design and the textiles, such as protective clothing, themselves, helping companies take the crucial step towards automation.

All info and the possibility to test the tool is available here:

https://www.itwm.fraunhofer.de/.../produkte.../texmath.html

Contact:

Fraunhofer Institute for Industrial Mathematics ITWM

Dr. Dietmar Hietel # Fraunhofer Platz 1 # 67663 Kaiserslautern

dietmar.hietel@itwm.fraunhofer.de # Phone: +49 631 31600-4627

 

 



One software for all cases – simulating technical textiles realistically

"TexMath" The software tool for technical textiles as well as nonwovens

M

Pressure measurement stocking for prevention and therapy support in diabetic foot ulcers

Pressure distribution measurement in the diabetic foot is an important tool for identifying and relieving areas of the foot at risk. A research project is working on the development of a textile sock with novel sensors that will enable continuous pressure measurement in patients' everyday lives. The aim is to detect elevated pressures, which can lead to pressure ulcers, at an early stage.

© @ISC
Prototype Pressure Track sock
Data flow at Pressure Track sock
© @ISC
Data flow at Pressure Track sock
Loading and unloading curve of the dielectric elastomer sensor as a function of the capacitance stroke and the pressure
© @ISC
Loading and unloading curve of the dielectric elastomer sensor as a function of the capacitance stroke and the pressure

IRINA LEHER1 | CHRISTOPHER FLEISCHMANN1 | BERNHARD BRUNNER2 | GOTTFRIED BETZ3 | HALIL BILGIN4 | YILMAZ SAGLAM4 | DETLEV UHL2 | TETIANA SHINKAR2 | STEFAN SESSELMANN1

1 Institute for Medical Technology, East Bavarian Technical University Amberg-Weiden.
2 Fraunhofer Institute for Silicate Research ISC
3 Strick Zella GmbH & Co.KG
4 ABECO Industrial Computer GmbH

1 Motivation
Approximately 8 million type 2 diabetics live in Germany [1]. The number of undiagnosed diabetes cases is estimated to be at least 2 million [1]. According to forecasts, the number of type 2 diabetics will increase to about 11.5 million by 2040 [1].
The secondary and accompanying diseases of diabetes include diabetic foot syndrome. Usually, several risk factors, such as microtrauma, peripheral arterial occlusive disease, and/or diabetic peripheral polyneuropathy, contribute to the development of diabetic foot syndrome [2]. Depending on the severity, foot deformities, ulcers or necrosis of parts or even the entire foot occur. Amputations are then inevitable. Charcot foot is considered a particularly severe variant of diabetic foot syndrome with numerous cumulative acute and chronic changes of the foot as a whole [3, 4].

Multidisciplinary therapy and prevention measures are intended to reduce the risk of amputations and the development of foot ulcers associated with diabetic foot syndrome. Risks such as altered biomechanics, increased pressure values in the foot area and inadequate blood glucose control must be identified and treated at an early stage [5]. In this way, lengthy healing processes of foot ulcers of up to approximately 14 weeks and further therapy costs can be avoided [6].
Plantar foot pressure values can be determined using in-shoe measurement systems and pressure measurement plates. Pedobarography with a pressure measurement plate is characterized by good spatial resolution [7]. However, pressure measurement plates are cost-intensive and not very flexible in their applicability. In-shoe measurement systems can be used in the patient's natural environment and provide a larger database for pressure assessment. Medical monitoring of plantar pressure values is usually performed only intermittently with longer intervals as part of preventive examinations.
To enable further multidisciplinary preventive measures to improve the quality of life of patients with diabetic foot syndrome, intelligent pressure measurement socks have been developed in the recent past [8]. These are designed for continuous use in everyday life to detect pressure peaks during activities of daily living and to initiate appropriate countermeasures. The socks were equipped with punctual sensors around the foot, which do not allow an area-wide pressure measurement. Due to the high costs expected for series production, further development of these pressure measurement socks was discontinued.
A current research project took up these challenges again. Standardized manufacturing process steps are to reduce production costs. In addition, the aim is to measure pressure over the entire foot area in order to identify individual risk areas for foot ulcers outside the sole of the foot, for example, in the special form of diabetic foot syndrome known as Charcot foot. In addition, other pressure measurement principles (for example, resistive systems)will be used to further explore their potential in use with smart textiles. The status of this PressureTrack project is presented below.

2 Material and Method

2.1 Structure of the PressureTrack sock
The PressureTrack sock (Figure 1) is made from a sustainably produced lyocell yarn blend (SMOOLS) using a flat knitting process, which has properties that are particularly important for diabetics, such as thermoregulation and antibacterial effect. Dielectric elastomer sensors are used for continuous pressure measurement. The sensors consist of stretchable elastomeric films made of skin-compatible silicone with alternating insulating and conductive individual layers [8]. When pressure is applied, the electrical capacitance of these soft sensors increases. The capacitance of a plate capacitor depends on its area and the distance between the two plates. When a force is applied to the sensor, both parameters change and so does the capacitance value. These capacitance values are then converted into an equivalent voltage value to make the pressure changes quantifiable. The current 16 large-area sensors are elastically bonded to the textile and distributed over the entire foot area. Cable routing takes place within knitted cable ducts and allows a high degree of elasticity when putting on or taking off the PressureTrack sock.

 

Contact:

Fraunhofer Institute for Silicate Research

Dr. Bernhard Brunner # Neunerplatz 2 # 97082 Würzburg

bernhard.brunner@isc.fraunhofer.de # Phone: + +49 931 4100 416

"AirfOx" - Development of a fiber-reinforced near-net-shape airfoil made of highly rigid oxide ceramics

Automation-capable process and technology for the production of near-net-shape engine blades for aircraft gas turbines (airfoils) from oxide ceramic fibers integral and suitable for series production

© @AWZ TFK

CMC for resource savings and reduction of CO2 emissions

In the field of aviation, weight reduction and energy efficiency are at the top of the list of requirements - also for new materials and components. Ceramic fiber composites (CMC) offer significant advantages for use in aircraft gas turbines: CMC components are only one-third as dense as conventional metal components, so they contribute to a significant reduction in weight. They can also be used at temperatures up to 300 K higher. In the hot section of gas turbines, CMC components therefore enable more efficient and complete combustion, save fuel and thus reduce CO2 emissions. Oxide ceramic composites (O-CMC) also naturally offer high oxidation resistance and a low tendency to corrosion in the combustion atmosphere, thus increasing the service life of the components.

Since the beginning of 2021, the Fraunhofer Center HTL has been working as part of the "AirfOx" project, funded by the Bavarian aerospace program BayLu25, to develop an automation-capable process and technologies that will enable near-net-shape production of engine blades for aircraft gas turbines (airfoils) from oxide ceramic fibers in an integral and series-production-ready manner.

Textile processing of ceramic fibers into near-net-shape 3D preforms for greater resource efficiency

By using multiscale simulation and CAD programs for load-oriented fiber design, the Airfoil example will be used to demonstrate how the development of a complex 3D preform can proceed in CMC manufacturing. Innovative weaving techniques will be used to develop a new manufacturing method for three-dimensional fabric preforms made of ceramic reinforcing fibers for CMC components with cover surfaces of different lengths, while at the same time allowing support structures in the form of webs to be woven in. Locally occurring stress peaks, which are detected during modeling, can also be taken into account in the fabric design. Transferring textile 3D weaving techniques to ceramic fibers is a particular challenge due to their brittleness. With the special manufacturing technology, the textile-ceramic 3D preforms are produced near-net-shape in one piece. This ensures high resource efficiency in the manufacturing process.

In the project, a digitization concept for the production of the preform is being developed in order to continuously record and evaluate the production data, which are essential for the component properties, during the weaving implementation of the textile semi-finished product. The aim is to set up a data management system as a preparatory measure for certifications to ensure the traceability of all process parameters, thus facilitating subsequent aviation certification.

The textile semi-finished product is converted into a CMC component in four steps, with the special process for infiltration being used for the first time for this type of 3D preform. In addition to the technology development of the infiltration process, the focus is on the automatability of the process.

"AirfOx" makes automated manufacturing steps of CMC components possible.

CMC airfoils can significantly contribute to reducing fuel consumption and lowering CO2 emissions. " AirfOx" will make a significant contribution here towards series production and should pave the way for establishing the new resource-efficient technology for manufacturing complex 3D fiber prefoms for CMCs, which can then also be used for other CMC types, e.g. SiC/SiC-CMC.

Fraunhofer Institute for Fraunhofer ISC - Center for High Temperature Materials and Design HTL, Application Textile Center Fiber Ceramics

Prof. Dr.-Ing. Frank Ficker # Kulmbacher Straße 76 # 95213 Münchberg

Frank.ficker@isc.fraunhofer.de # Phone: +49 (0)175 1137192

Intelligent electronic plaster APFEL

Accelerated and improved wound healing with the electronic patch APFEL

© @ENAS
© @ENAS

The newly developed intelligent electronic plaster APFEL accelerates and improves wound healing. In collaboration with partners, additive processes are being developed for the manufacture of multilayer flexible electronic systems and the individual components are being evaluated with regard to biocompatibility. To demonstrate the in vitro effect, among other things, a scratch assay was used as an in vitro wound healing assay and the accelerated closure of a gap (scratch) introduced into a cell lawn of keratinocytes (HaCaT cells) was demonstrated. Fraunhofer ENAS developed adapted screen printing processes for the fabrication of conductive and insulating multilayer films on flexible substrates, electrical throughhole plating variants for thin film substrates and assembly and interconnection technologies for the hybrid integration of conventional electronic components and corresponding control electronics for testing the demonstrators.

The healing of wounds is an ancient problem that is still not completely understood and solved. Even in ancient times, wounds were rinsed with alcohol, bandaged and stitched. In acute wounds, healing takes place within a few days to weeks, depending on the size of the injury. One speaks of chronic wounds if there are no healing tendencies after  three months or if the wound still exists and has not healed.1 The property of an electrical gradient to induce cells in regenerative tissue to migrate and polarize in a directed manner is the target for the therapy forms developed in the BMBF project APFEL2 to induce accelerated and improved wound healing via an “intelligent electronic plaster”.

1 Schiemann D, Deutsches Netzwerk für Qualitätsentwicklung in der Pflege. Expertenstandard Pflege von Menschen mit chronischen Wunden. DNQP; 2009.

2 BMBF “KMUinnovativ: Medizintechnik”, Förderkennzeichen 13GW0106C.

Contact:

Fraunhofer Institute for Electronic Nano Systems ENAS

Dr. Alexander Weiß # Technologie-Campus 3 # 09126 Chemnitz

alexander.weiss@enas.fraunhofer.de # Phone: +49 371 45001-246

Degradation sensors in asphalt base layers

Use of textile semi-finished products at the Fraunhofer WKI

© @WKI
© @HOFZET

Textile semi-finished products can make a major contribution to weight savings in the end product. In addition to carbon fibers, natural fibers are increasingly coming into focus for lightweight products. In particular, the use of flax fibers from the European region can have a positive CO2 balance in production compared to carbon fibers produced in an energy-intensive production process. The requirements for textile semi-finished products in the automotive sector are to achieve specified mechanical characteristic values while maintaining the same component size and thickness and, at the same time, to generate ecological and also economic advantages through weight savings and the use of sustainable materials. Weave types are used that are characterized by the desired weight per unit area, a high drapeability and a design suitable for the respective load cases.  In addition to the automotive sector, textile semi-finished products can also be used in "new" applications in the construction sector. The matrix used here includes cement or asphalt, which are characterized by a relatively large particle size. In order to prevent structural disturbance by the textile semi-finished product in the respective layer, it must be ensured that the respective grain size can penetrate the fabric. At the same time, there are high demands on the resistance to displacement of the fabric, since during handling and installation of the fabric in structural and civil engineering, sometimes enormous forces act on the textile semi-finished products, which must not lead to a disturbance of the fabric structure. A so-called leno weave is therefore a very good option for these applications, as it allows large yarn spacing with simultaneously high displacement resistance. In addition, when producing a leno fabric, the warp and weft yarns can be specifically selected with regard to their fineness (tex) and can thus absorb enormous force influences during the installation and service phases. One project in which these leno fabrics are being developed and manufactured by the Fraunhofer WKI for use in concrete is the DBU-funded project on the use of natural fiber reinforcement in concrete/façade slabs (FKZ 35830/01-25). Here, leno fabrics made of flax fibers are used as an alternative to steel reinforcement. The advantages are a slimmer and lighter construction of concrete components, since cement can be saved by reducing the reinforcement cross-sections. In addition, the corrodibility of the textile fibers used is significantly reduced, while their tensile strength is comparable to that of steel. The minimum cover required for steel reinforcement to prevent corrosion can therefore be dispensed with. In addition to the use of textile fibers for force absorption, functional integrations such as lighting with technical textiles or degradation monitoring are also feasible. In the SenAD research project at the Fraunhofer WKI, sensor wires were integrated directly into the textile semi-finished product in the weaving process and incorporated into asphalt test specimens by the project partners (FKZ 19F1070A). The medium-term goal of this incorporation is continuous monitoring of the asphalt condition under the constant influences of traffic and weather. The change in the electrical resistance of the sensor material can provide information on the degradation state of the asphalt base layer and thus make remediation measures more sustainable.

Contact:

Fraunhofer Institute for Wood Research-Wilhelm-Klauditz-Institute WKI, HOFZET

René Schaldach # Heisterbergallee 12 # 30453 Hanover

rene.schaldach@wki.fraunhofer.de # Phone: + +49 511 9296 2220

Innovative scPLA fiber based monomaterial composite

Development of bio-based fiber materials from polylactic acid (PLA)

© @IAP
© IAP
© @IAP

An increasing industry demand for sustainable alternatives to conventional petroleum-based products justifies the high value of innovative bio-based yet high-performance materials.

One promising candidate in this regard is polylactic acid (PLA), a bio-based polyester that is commercially available and can be processed into fibers, films, or injection molded parts through thermoplastic processing. Targeted stereocomplexation also allows the melting temperature to be increased by up to 60 K to 230 °C, effectively improving thermal properties of PLA-based products.

Based on the thermally resistant stereocomplex (sc)PLA filament yarns, researchers at the Fraunhofer Institutes IAP and ICT are developing innovative PLA-based single-component organic sheets that address technical applications and can contribute to the implementation of the UN's Sustainable Development Goals, particularly with regard to recyclability.

Current developments in this area are taking place within the framework of the Fraunhofer Circular Plastics Economy CCPE® cluster. These focus on optimizing the mechanical performance of the composite material. A preferably attractive tensile and ductility property profile should contribute to establishing new application areas for PLA-based products.

However, a final application of the presented material also requires the commercial availability of scPLA filament yarns. The BMEL-funded AllPLACo project (FKZ 2220NR297X) is expected to make a decisive contribution to this over the next 2 years. In this project, the Fraunhofer IAP is working alongside the filament yarn manufacturer Trevira GmbH on, among other things, verifying the scalability of the manufacturing process for scPLA filament yarns.

The Fraunhofer Textile Network booth (Hall 12.0 Booth D15) will feature exhibits of scPLA filament yarns created as part of the "AllPLACo" project, as well as innovative PLA-based monomaterial composites in the form of organosheets, which are being developed in cooperation between the Fraunhofer Institutes IAP and ICT in the Fraunhofer Cluster Circular Plastics Economy CCPE®.

Contact:

Fraunhofer Institute for Applied Polymer Research IAP

Dr. André Lehmann # Geiselbergstraße 69 # 14476 Potsdam-Golm

lehmann@iap.fraunhofer.de # Phone: +49 331 568 1510

 

SEAM Screw Extrusion Additive Manufacturing

With the new SEAM (Screw Extrusion Additive Manufacturing) technology, the STEX Group is setting a milestone for ultra-fast 3D printing. Here, additive manufacturing processes are developed with the latest laser sintering and fused layer technology and a focus on material development, increased efficiency, resource conservation and functional integration.

© @IWU
© @IWU

ULTRA-FAST 3D PRINTING USING STANDARD GRANULES

The SEAM system consists of an extrusion-based plastification unit for processing plastic granules, which was combined with a hexapod. The hexapod, i.e. a 6-axis parallel kinematics that can be swiveled, is equipped with a metal construction platform. The hexapod motion system is characterized by high dynamics and low moved masses, which is associated with high accuracy regarding positioning and path. These properties imply that this system is ideal for motion control of the extruder.

Process principle

The plastic granules are fed into the extruder via a modified extruder screw. Then they are plasticized with achievable process speeds of up to one meter per second. Subsequently, the arising plastic melt is de[1]posited layer by layer onto the construction platform. The parallel kinematics enables tilting of the construction platform along the x-, y- and z-axis, and specifically moves it beneath the nozzle of the plastification unit so that the component shape is generated, which has been programmed before. Due to the continuous deposition process it is possible to manufacture large-volume reliable components. Controlling of the extrusion performance depending on the path speed is required in order to ensure controlled printing of curves and corners, and to allow for jumps in position without material deposition. Due to the highly inert plastification behavior of extruders it is not reasonable to change the volume via the extruder speed. For this purpose an upstream unit was developed, which allows material deposition between 0 and 100 percent depending on the speed.

Processable materials

The SEAM method can process free-flowing, cost-efficient standard plastic granules. This permits saving material cost by up to 200 times compared to conventional fused layer modeling (FLM) processes that use expensive filament. Various plastics have already been tested – ranging from thermoplastic elastomers, to polypropylene and polyamide-6 with a 40-percent content of carbon fibers (PA 6 CF). These are industrially relevant materials characterized by high stiffness and strength or a high elasticity, they cannot be processed by conventional 3D printers.

Process advantages

 A major advantage of the SEAM process lies in its processing speed. Up to ten kilograms of plastics per hour are extruded through the one millimeter sized tempered nozzle of the plastification unit. In comparison, conventional FLM, a method for depositing melt strands, requires 20 hours for printing one kilogram of plastics. Moreover, SEAM makes it possible to manufacture reliable complex geometries without using any support systems. Various wall thicknesses can also be generated within one printed path. While components conventionally manufactured by plastics injection molding exhibit rather thin walls due to the process and design, the SEAM process can realize strand widths between 1.2 and 3.1 mm for PA 6 CF by using a nozzle of one millimeter in size, depending on table speed and extrusion performance.

Summary

The SEAM process significantly extends the possibilities for efficiently manufacturing plastic components in a 3D printing process. The overall component cost can be considerably reduced due to the low material cost and the short production times. Moreover, this method can be used to process materials that could previously not by processed by 3D printing. The surface qualities achieved with this process are the same as those obtained by the standard FLM process. 3 Demonstration components.

Contact:

Fraunhofer Institute for Machine Tools and Forming Technology IWU

Dr.-Martin Kausch Reichenhainer Str. 88 # 09126 Chemnitz

martin.kausch@iwu.fraunhofer.de # Phone: +49 371 5397 1024

Calender Impregnation Plant

The calender direct impregnation system enables continuous and thus cost-optimized production of fiber-reinforced thermoplastic semi-finished products. Various modules are available for additional pre- and post-treatment of the materials in the process chain. Flat semi-finished products, such as (hybrid) fiber fabrics or fabrics, nonwovens and thermoplastic film are ideally fed to the process on a roll. It is also possible to feed individual cuttings. In an infrared module upstream to impregnation calender, coatings of the fiber material can be burned off or plastic can be preheated. The material is further heated in the impregnation calender and pressed between two steel belts in a roller system. The impregnation calender is followed by the calibration calender for further pressing to a desired height and smoothing of the surface. At the end of the production chain there are edge trimming, cross cutting modules and a module for winding the material. The material produced is therefore taken from the system in the form of plates or wound on a roll. Adding or removing individual modules or changing the order of the modules enables the processing of various materials in a flexible, needs-based production chain.

Calender Impregnation Plant
© @ IWU

More information at:

https://www.hybridleichtbau.fraunhofer.de/en/machinery/calander-impregnation-plant.html

Contact: 

M. Sc. Alexander Husemann

Composite materials, mass production technology for FRP, function integration

Fraunhofer Project Center Wolfsburg c/o Open Hybrid LabFactory e.V.

Hermann-Münch-Str. 2 # 38440 Wolfsburg # Phone: +49 172-14900133

JEC 2023

From April 25 - 27, the Fraunhofer Institutes IWU, IAP, ITWM and ISC participated in the world's leading composites trade fair JEC in Paris.

© Fraunhofer ISC
Fraunhofer ISC and Hof University

The picture shows the team of Fraunhofer ISC-HTL, Eva Paulack and Dr. Jens Schmidt, who presented the R&D work at the Textile Campus Münchberg together with the staff of Hof University of Applied Sciences, Alexandra Luft and Professor Claus-Ekkehard Koukal. With more than 30 new contacts, among others to international companies and institutes, the fair was very successful for the cooperation partners.

INDEX 2021 International Nonwovens Event

Geneva, Switzerland / October 19, 2021 - October 22, 2021

The trade fair INDEX in Geneva is an international trade fair for nonwovens. About 580 exhibitors will present their latest products and services at the fair. The team from the department »Transport Processes« of Fraunhofer ITWM presents their expertise and research on technical textiles and nonwovens.

--> For more information click here!

E-textiles: So hot right now!

October 01, 2021

Fraunhofer IZM and the weißensee academy of art in Berlin have opened a unique open innovation lab for prototyping textile electronics. Fitted with the latest in high-tech equipment and machines, the Textile Prototyping Lab (TPL) can turn e-textile visions into real fabrics and garments with its interdisciplinary team of scientists and artists.

--> For more information click here!

Learn more about the Textile Prototyping Lab:  www.textileprototypinglab.com

With Mathematics Against the Crisis

Meltblown Productive – ITWM Software Supports Nonwoven Production for Infection Protection

© Fraunhofer ITWM
Simulation of many filaments in the meltblown production process.

Simulations by the Fraunhofer Institute for Industrial Mathematics ITWM make processes in the manufacturing of nonwovens more efficient. Within the anti-corona program of Fraunhofer the production of infection protection is optimized.

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Fair presentation of the Fraunhofer Technical Textiles Alliance at Techtextil

© Fraunhofer Technical Textiles Alliance

The Fraunhofer Technical Textiles Alliance is presenting current research topics at its joint booth at Techtextil 2019 in Frankfurt. Following the motto of the fair "Space for Innovation", all competence fields of the alliance offer an interdisciplinary platform for new ideas and developments.

-> Press Release Techtextil 2019 

Elastic sensors for smart textiles

© Fraunhofer ISC

Smart materials and embedded electronics create the conditions for innovative design and new applications in the field of intelligent textiles, electronic interconnections, controls and displays. The Fraunhofer Institute for Silicate Research ISC with its Center Smart Materials is working on silicon-based materials, adapted printing pastes and efficient production technologies in order to exploit the application potential of stretchable sensors and conductive paths, to inspire new product ideas and to accelerate the implementation.

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Wireless power transmission for technical textiles

© Fraunhofer ENAS

The trend towards the "Internet of Everything" is ongoing. Whether in industrial, medical or everyday applications, more and more electrical devices are connected to each other, record sensing values, exchange data and react to them. Due to smaller structures, new processing possibilities and new flexible materials, such systems are also being used more and more frequently in the textile sector. For example, medical measurements can be recorded directly on a garment, actuators such as EMS electrodes can be integrated directly into the textile or functions such as MP3 players, GPS receivers, fall detectors, heating structures and much more can be embedded simply and intuitively in textiles. Communication and data exchange usually take place wirelessly via WLAN, Bluetooth, RFID or, in the future, via the 5G network.
Electrical energy is required for such applications and functions. Despite the efforts to further minimize the energy demand of electronic circuits, it is not always possible to operate these systems completely energy autonomously. Therefore, energy storage devices such as batteries or rechargeable accumulators are necessary for operation.

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Parylene based technologies for smart coatings and wearables

© Fraunhofer ENAS

A promising approach for the integration of functional elements such as sensors and actuators is the production of electronic systems by embedding active and passive electronic components in polymer coatings using established deposition technologies.

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Environmentally friendly Chitosan: Insects supply chitin as a raw material for the textile industry

© Fraunhofer IGB

Fossil-based chemicals are often used in textile processing. That is why the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB is researching sustainable biobased alternatives. The Institute is working on utilizing side streams from the animal feed manufacture for the production of chitosan. The biopolymer is supposed to be used as a sizing agent in the processing of yarns or for the functionalization of textiles.

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Simulating and optimizing industrial spinning process

Spinning polymer filaments, for example for personal care products, is highly complex: simulating the process involved is too much for currently available computing power to handle. Fraunhofer researchers have successfully applied new approaches to simplify te calculations necessary for simulation. Now for the first time complete spinning processes can be simulated, providing a better understanding of the processes and greatly simplifying their optimization.

-> Press Release of Fraunhofer ITWM

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Designing polymer spinning packages for flow dynamics

© Fraunhofer ITWM

Melt spinning is the most common process for producing fibers from plastic. The Fraunhofer Institute for Industrial Mathematics ITWM uses simulation and optimization methods to support customers in the development, design and improvement of spinning packages.

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Machine Learning in Textile Industry

© Fraunhofer ITWM

Dramatic changes are taking place in the demands placed on the textile industry. The trend is towards individualization in many areas, similar to car purchasing, for example. Consumers are increasingly demanding tailor-made products. This change in consumer behaviour is lucrative for European textile companies, since the customer-specific manufacture of products with small batch sizes leads to a relocation of production back to Europe. However, this requires the digitization of production, which the Fraunhofer Institute for Industrial Mathematics (ITWM) supports with hybrid simulation-based Machine Learning (ML) methods.

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Halogen-free flame retardant coating for woven and nonwoven fabrics

© Fraunhofer IST

Coating features of Atomic Layer Depostion (ALD):
- Oxide passivation as diffusion barriers
- High uniformity and conformity on 3D geometries
- Transparent ultrthin films (< 10 nm)
- Low-temerature process window (< 70 °C)

 

Cost-effective carbon fibers for lightweight construction

© Fraunhofer IAP

The ComCarbon® technology from the Fraunhofer Institute for Applied Polymer Research IAP will make it possible in the future to produce carbon fibers at low cost for the mass market.

-> Press Release of Fraunhofer IAP 

Symposium: Smart textiles in structural components

© Fraunhofer Technical Textiles Alliance

Resource-efficient and sustainably produced, equipped with functional and smart properties - the textiles of the future will have to meet high demands. The first symposium of the Fraunhofer Technical Textiles Alliance took place in Braunschweig under the motto »Smart textiles in structural components«. On 6 and 7 June 2018, experts from the industry gave insights into advanced textile technologies.

Resource-efficient and sustainably produced, equipped with functional and smart properties - the textiles of the future will have to meet high demands. The first symposium of the Fraunhofer Textile Alliance took place in Braunschweig under the motto "Smart textiles in structural components". On 6 and 7 June 2018, experts from the industry gave insights into advanced textile technologies.

International Textile Conference

AACHEN - DRESDEN - DENKENDORF INTERNATIONAL TEXTILE CONFERENCE, AACHEN from 29th to 30th NOVEMBER, 2018

Evgueni Tarkhanov, André Lehmann, Fraunhofer IAP, Potsdam

Evgueni Tarkhanov from the Fraunhofer Institute for Applied Polymer Research gave a lecture about "PLA filaments yarns - Halfway to technical fibres" on the topic Functionalization & New Materials: New Fibres at the International Textile Conference on 29/11/2018 in Aachen.

Fraunhofer Technical Textile Alliance exhibited at Techtextil 2017

© Fraunhofer Technical Textiles Alliance

The Fraunhofer Technical Textiles Alliance, founded in spring last year, with currently 14 member institutes, enjoyed a positive response at this year's leading international trade fair for technical textiles and nonwovens TECHTEXTIL.

-> Press Release Techtextil 2017 

Simulation of fibers, knitted and warp-knitted fabrics - mathematics in technical textiles

The High Performance Center Simulation and Software Based Innovation hosted the Industrial Workshop Digital Technologies for Fibers, Nonwovens and Technical Textiles at the Fraunhofer Center. For two days, it offered experts from industrial development and application-oriented research the opportunity for practical exchange.

Recent developments such as the coupling of simulation techniques for the computer-aided investigation of the effects of the manufacturing process on the product properties were in the foreground. An equally important goal of the workshop was to focus on the views of experts from industry. This was achieved by interesting presentations from representatives of leading companies in the field of nonwovens and technical textiles such as BJS Ceramics, BSN medical, Sandler, OLU-Preg Composite Group, Oskar Dilo Maschinenfabrik or MANN+HUMMEL.

-> Link to the High Performance Ceter Simulation and Software Based Innovation