Wageningen University: Adding Some Sparkle to 3D Printed Objects with Gold Nanoparticles

Nanotechnology may seem novel and advanced, but it has actually been used for thousands of years. Metallic nanoparticles are present in glass and pottery from hundreds and thousands of years ago, giving the items a shiny, glittering look. In a paper entitled “Plastic embedded gold nanoparticles as 3D printing dichroic nanocomposite material,” a group of researchers discusses how they fabricated a 3D printable nanocomposite composed of dichroic gold nanoparticles and a 3D printable polymer.

“Dichroic AuNP (gold nanoparticles) were prepared using a modified Turkevich method, thus reducing gold ions to gold nanoparticles using citrate as both reducing and capping agent,” the researchers explain. “In the classical Turkevich method, a boiling chloroauric acid solution is reacted with citrate using a molar ratio citrate to gold of 10, producing AuNP of around 10 nm. When this ratio is changed, the size of the obtained nanoparticles changes as well. We discovered that a citrate/gold ratio between 0.6 and 0.8 produced dichroic nanoparticles that showed a brownish reflection and a purple transmission.”

The nanoparticle solution was studied by transmission electron microscope (TEM).

“The presented synthesis is easy and fast, as it takes only few minutes to obtain the dichroic solution after the addition of the citrate,” the researchers continue. “During the synthesis, the solution changed color multiple times: the yellow solution of the gold ions become blue one minute after the addition of the citrate solution. Two minutes later, the solution showed an intense black color, before becoming dichroic after another two minutes of boiling. The color changed during the synthesis hint that the dichroic nanoparticle formation is not just seeded growth, but a more complex mechanism.”

Once the gold nanoparticle solution was prepared, the nanoparticles were embedded in a 3D printable material that could be used with a standard off-the-shelf FDM 3D printer. The researchers used polyvinyl alcohol (PVA) as the carrier, as it is one of the most commonly used 3D printing materials, it is water soluble and can thus be mixed with the nanoparticles without need of changing solvent, and because it can be used as a capping agent for nanoparticles.

The researchers compared TEM results of the original dichroic solution to the AuNP-PVA dissolved in water, and found that the nanoparticles were still of the same size and shape as the original ones, showing that the embedding in PVA does not influence the stability of the nanoparticles. Finally, they extruded the material to create a filament for FDM 3D printing. The small percentage of gold did not affect the printability of the PVA. The researchers then 3D printed a replica of the fourth-century Lycurgus cup and coated it in PDMS so it could hold water.

“In conclusion, we showed how to synthesize and embed dichroic nanoparticles in 3D printable material,” the researchers conclude. “The AuNP-PVA nanocomposite is mechanically similar to the bare plastic and its dichroic optical properties are similar to the one shown by the AuNP solution. The 3D printed objects can be coated to achieve water impermeability and stability at room temperature for long time. We can envision this methodology to be used not only by artists, but also for studying optical properties of nanoparticles or, for example in 3D fabrication of optical filters.”

Authors of the paper include Lars Kool, Anton Bunschoten, Aldrik H. Velders and Vittorio Saggiomo.

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Prints With Programmable Rigidity Control Present Medical Applications

One of the core problems with fixing complex cardiac tissues and vessels is that of getting replacement parts to behave like the real thing. Take heart disease for example: hardening blood vessels present an issue that makes them hard to replace. That’s why a team of researchers at Colorado University is using 3D printing as […]

The post Prints With Programmable Rigidity Control Present Medical Applications appeared first on 3D Printing.

Concrete and 3D Knitting Combine to Produce KnitCandela 3D Printed Structure

In Mexico City, a strange structure has been erected – it looks a bit like a crouching frog, or maybe an exotic flower. It was built using a special 3D knitting technique developed at ETH Zurich. The structure, called KnitCandela, is partially made from concrete, but its formwork is a knitted textile supported by a steel cable-net. The project, an homage to Spanish-Mexican architect Felix Candela, is a collaboration with Zaha Hadid Architects Computation and Design Group and Architecture Extrapolated.

3D knitting has been used before to produce things like clothing and furniture, but it isn’t often seen on this large of a scale. It took 36 hours for an industrial knitting machine to produce the shuttering of the formwork for the shell structure, following a digital pattern. The fully shaped, double-layered textile was knitted in four long strips, with the lower layer forming the visible ceiling. The upper layer contains sleeves for the cables of the formwork system and pockets for balloons. After the structure is coated in concrete, the balloons are popped, leaving hollow spaces that help save on material and weight.

The structure was erected in the courtyard of a museum; the knitted formwork was tensioned between a temporary boundary frame and sprayed with a specially formulated cement mixture, just a few millimeters thick. Once it hardened, conventional fiber-reinforced concrete was applied. The knitted fabric, which was brought to Mexico City inside normal suitcases, weighs about 25 kilograms and the cable around 30 kilograms. Together, they are able to support more than five tonnes of concrete.

KnitCandela’s technology was developed by Mariana Popescu, a doctoral student with Philippe Block, Professor of Architecture and Structure at ETH Zurich, and Lex Reitier, a doctoral student with Robert Flatt, Professor of Physical Chemistry of Building Materials. The technology is an evolution of the flexible forming technology developed for the HiLo roof, which the Block group developed for Empa’s NEST research and innovation building in 2017. Unlike the HiLo roof, which was made of a network of cables and a sewn textile, KnitCandela’s knitted shell was produced in one go.

Using knitted textiles in construction simplifies the construction process for complex shapes, and also cuts down on material, labor and waste. It’s a lot faster, too.

“It took only five weeks from the initial work until completion – much less time than if we were using conventional technology,” said Matthias Rippmann, project manager for KnitCandela and senior researcher in the Block Research Group.

While 3D printing is being pursued with interest in the construction industry right now, 3D knitting is a new idea, but a promising one. Giant robotic 3D printers aren’t required for 3D knitting a structure like KnitCandela, either – all that is needed is a conventional knitting machine.

“Knitting offers a key advantage that we no longer need to create 3D shapes by assembling various parts,” said Popescu. “With the right knitting pattern, we can produce a flexible formwork for any and all kinds of shell structures, pockets and channels just by pressing a button.”

Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.

[Source/Images: ETH Zurich]

 

A 3D Printed Symphony of Violins Will Sound in Ottawa for 3D String Theory Concert

(L to R) Marlena Pellegrino, Hanna Williamson, Natalie Deschesnes, Alisa Klebanov, Geena Salway [Image: Mark Holloway]

Several musicians and 3D printing enthusiasts have combined their love for both of those things by creating 3D printed musical instruments – and violins are some of the most common. These talented makers have created instruments that often sound as beautiful as their traditional counterparts – but have you ever wondered what several 3D printed violins would sound like in symphony? That’s what Laurent Lacombe, Co-Founder of Creadditive, and violin maker Charline Dequincey wanted to find out, so they spent several months 3D printing and fine-tuning eight violins for the Ottawa Symphony Orchestra. The orchestra will play the 3D printed instruments in a performance called 3D String Theory, which will take place on November 4th.

Composer Harry Stafylakis (left), a 3D printing technician, and soloists (L-R: Jessie Ramsay, Mary-Elizabeth Brown, and Lisa Moody) at the Industrial Technology Centre in Winnipeg where the instruments were printed. [Image courtesy of Ottawa Symphony Orchestra]

Creadditive is based in Gatineau with a satellite office in Quebec City. The company specializes in using 3D printing for things like heritage restoration, but creating eight 3D printed violins wasn’t a huge change for Lacombe.

“Whether you’re designing a part for heritage, or a mechanical part in a car, or implants in the medical field or a violin, it’s basically the same techniques,” he said.

Lacombe started by CT scanning Dequincey’s conventional violin, then converting the 2D file into a 3D model. It wasn’t quite as simple as just hitting “print” after that, though – plastic is heavier than wood, so the violins needed to be modified so as not to be too heavy. Dequincey gave regular feedback in order to achieve the best compromise between weight, design and sound.

“Honestly, the first time I heard the sound, I was really impressed,” said Lacombe.

The sound produced by the 3D printed violins isn’t identical to that produced by a traditional wooden violin, Lacombe said, but that wasn’t the goal of the project – the goal was to see what a new, digital manufacturing form could accomplish when combined with a traditional musical instrument. He doesn’t think that 3D printing will ever replace traditional handcrafting, as the sound just isn’t the same, but he does think that 3D printed violins could be valuable for entry level musicians who can’t yet afford a traditional violin.

Music is one of the oldest art forms, so it will be interesting to see how the newest technology can alter the sounds of such a traditional instrument. 3D printed violins may not replace handcrafted wooden ones, but they can bring a new dimension to them – and make more people realize that 3D printing is capable of creating something truly functional and valuable.

“People are starting to be aware that additive manufacturing is not a toy or a joke on the internet anymore,” said Lacombe.

Eight women will perform in the 3D String Theory concert.

“The discovery of alloys like bronze and brass allowed ancient music-makers to expand the possibilities of horn and wooden aerophones,” the concert website states. “The Industrial Revolution introduced new materials and manufacturing processes that helped to redesign instruments like the piano, brass, and woodwinds so that they could play more notes—faster and louder. And as these capacities for shaping sound have grown and changed, so too has composers’ capacity for musical expression. 3D StringTheory explores how today’s new technologies, like 3D printing, can further expand musical boundaries.”

You can buy tickets for 3D String Theory here.

Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.

[Source: Ottawa Business Journal]

 

A closer look at the developing electronics 3D printing industry

Electronics 3D printing is an area of additive still in its infancy. With plenty of space for potential commercial competition, it is interesting to note upcoming developments in the field from the research sphere. Last month, 3D Printing Industry published an article about a team from the University of Texas at El Paso (UTEP) who demonstrated the […]

Materialise unveils the 3D printed mammoth at the Lier Museum

Materialise, a Belgian software and 3D printer maker, has unveiled its mammoth project in the city of Lier, Belgium. Earlier this year, the company was hired to 3D print a replica of Lier mammoth. The project is now complete, and the 3D printed mammoth can now be visited at the Stadsmuseum Lier. Gertjan Brienen, Project […]

DIY Linear Servo Actuator #3DPrinted via @PotentPrintable

Ali shared on Thingiverse:

Linear Servo Actuators

This video shows how to assemble and then run these DIY linear servo actuators (pusher style). Two sizes have been designed and made available for any project you have that needs a pusher style linear actuator.

An off the shelf version can cost around $70, while these 3D printed versions are much lower cost. Links to the STL files, part lists and affiliate links can be found below.


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Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers!

Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D!

The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3D printer! If you’ve made a cool project that combines 3D printing and electronics, be sure to let us know, and we’ll feature it here!

Halloween Eyes with ItsyBity via @sudomod_wermy

Wermy shared on YouTube:

Spooky Arduino Halloween Eyes

Links to everything you need: https://www.sudomod.com/spooky-arduino-halloween-eyes/
Follow me on Instagram to see what I’m up to between videos: https://www.instagram.com/sudomod_wermy/
Discord server: https://discord.gg/8BDrDjQ


649-1
Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated with 3D printed enclosures, brackets, and sculptures, so each Thursday we celebrate and highlight these bold pioneers!

Have you considered building a 3D project around an Arduino or other microcontroller? How about printing a bracket to mount your Raspberry Pi to the back of your HD monitor? And don’t forget the countless LED projects that are possible when you are modeling your projects in 3D!

The Adafruit Learning System has dozens of great tools to get you well on your way to creating incredible works of engineering, interactive art, and design with your 3D printer! If you’ve made a cool project that combines 3D printing and electronics, be sure to let us know, and we’ll feature it here!

3D Printing News Briefs: October 31, 2018

Happy Halloween, fair readers! We’re giving you a treat today instead of a trick – our latest edition of 3D Printing News Briefs. First up, Materialise has completed a mammoth 3D printing project, and Australian manufacturing company C-Mac is embracing the technology for the first time. atum3D has revealed what new product it will be bringing to the upcoming formnext 2018. Finally, a group of French researchers compared powder bed fusion and binder jet 3D printing as possible methods for fabricating sand molds.

Materialise Unveils Life-Size 3D Printed Mammoth

The massive Mammoth of Lier, named for the Belgian city where it was discovered, lived during 20,000 BC, and has been on display at the Royal Belgian Institute of Natural Sciences in Brussels since 1869. But thanks to the hard work of Belgian 3D printing company Materialise, the woolly mammoth skeleton is now back home in Lier…a 3D printed version of it, anyway. Earlier this summer, a multidisciplinary team of Materialise engineers and production operators, paleontologists, and archaeologists began work on the mammoth 3D printing project, which is Materialise’s largest yet at 3.5 meters tall. Materialise optimized the 3D scans of each of the mammoth’s 320 bones in order to replicate its fossilized skeleton, then digitally reconstructed it and prepared each file for 3D printing.

“When I heard that the mammoth of Lier would be 3D-printed, I was amazed. 3D printing has already been used for reproducing missing bones, but here we were talking about an entire mammoth, and I think it’s the first time this has been achieved,” said Dr. Mietje Germonpré, paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels. “3D printing gave us the opportunity to create a new, more scientifically accurate reconstruction of the mammoth’s anatomy.”

Fittingly, Materialise used nine of its large-format Mammoth SLA 3D printers, the only machines it makes but does not sell, to complete all 1,260 hours of 3D printing. The company’s Design & Engineering team also created a modular carbon fiber structure that could support the skeleton from the interior. Now, the 3D printed replica of the mammoth is back in Lier, just in time for the doors to open at its new city museum.

C-Mac Embraces 3D Printing

Australian manufacturing company C-Mac Industries Cooperative Ltd, headquartered in Sydney, recognized that times were changing in the industry, and not exactly for the better. Between 2008 and 2013, the country lost one manufacturing job every 19 minutes, and C-Mac realized that it needed to evolve. So in the middle of 2017, all of the staff members agreed to become business owners, and C-Mac went from being a family-owned company to a more socially responsible workers’ co-operative. In order to sustain and keep growing its business, C-Mac spent a ten-month period adopting 3D printing and creating parts for over ten different industries, as the technology is rapidly becoming a preferred approach to developing product models.

“You have to embrace change,” said C-Mac’s General Manager Steve Grlyak. ” We have seen so many manufacturing companies in Sydney go bankrupt because they are not willing to change or are slow to adapt to change or have over capitalised on the wrong equipment.

“It is only the beginning. We are also looking into having a 3d printing scholarship award to provide help to students in Australia along with striving to build a bridge between knowledge and practice. The future is upon us.”

It’s not easy to adopt a new type of thinking, but C-Mac knew that 3D printing was the future of the industry and, with the help of its 50 years of experience in manufacturing, stepped up to the plate.

atum3D Introducing Latest Software at formnext

At the upcoming formnext 2018, open platform DLP 3D printing specialist atum3D will be introducing its new, redesigned Operator Station software, which comes with proprietary MAGS AI technology. Thanks to an intuitive user interface and touchscreen support, the software makes it easy for users to prepare print jobs for the company’s DLP Station 3D printers. Operator Station lets users duplicate parts, or fill available build volume, with the click of a button, and its MAGS AI will automatically adjust a part’s orientation and generate the necessary supports.

“We’re very excited to be back in Frankfurt for the third time in a row to show our most recent developments. This year, the main spotlight is on software, one of the three pillars on which atum3D was built, together with hardware engineering and resin chemicals. When creating the all new Operator Station software from the ground up, we took special care to incorporate our user’s feedback and requests. That’s why we created a highly intuitive interface that takes you from part import to final print job in just a few clicks. The intelligent approach of our proprietary MAGS AI technology, which is the abbreviation of Mark, Adjust & Generate Supports, plays an essential role,” said Tristram Budel, CEO at atum3D.

““MAGS AI now analyses the part’s shape, keeps my selection free of supports, suggests the optimal orientation and adds the necessary supports. That’s about as fast and easy as it gets!”

At formnext, atum3D will also be introducing its new Industry Excellence Pack for material scientists and research institutes, as well as an open resin platform for the DLP Station 5, which will be showcased at the event. Visit atum3D at booth 3.1-B19 to see its new Operator Station with MAGS AI and the DLP Station 5.

Comparing Powder Bed Fusion and Binder Jetting for Sand Molds

A trio of researchers from Centrale Nantes and École Normale Supérieure de Rennes in France recently published a paper, titled “A review on the additive manufacturing of sand molds by binder jetting and selective laser sintering,” that analyzes the current techniques of the casting industry for using 3D printed sand molds. Specifically, they looked at SLS and binder jet 3D printing. In the paper, the researchers analyzed patents, case studies, and scientific articles, as there is limited data about 3D printed sand molds in other studies. The research team got together because there’s a lack of resources and interest in 3D printing sand molds, and they wanted to provide a more comprehensive analysis of the topic. The paper highlighted the current gaps in the field, as well as proposed some key perspectives for possible social implications.

“The review investigates new factors and methods for mold design, looking at mechanical properties and cost analysis as influenced by material selection, thermal characteristics, topological optimization and manufacturing procedure,” the researchers state in the paper. “Findings in this study suggest that this topic lacks vigorous scientific research and that the case studies by manufacturers thus far are not useful.”

Co-authors of the paper are Tugdual Amaury Le NéelPascal Mognol, and Jean-Yves Hascoët.

Discuss these stories and other 3D printing topics at 3DPrintBoard.com or share your thoughts in the comments below.

Sterne Bringing Silicone 3D Printing to COMPAMED Trade Fair

Sterne Elastomere, a company located in the south of France, specializes in manufacturing items out of silicone materials for industries such as food and drink, mass transit, medical, nuclear, and pharmaceuticals and cosmetics. Two years ago, Sterne made its move into the 3D printing world and debuted its SiO-Shaping 1601 silicone 3D printer at K 2016, a top plastics and rubber trade show, for the first time.

In order to provide its clients with 3D printed silicone prototypes that possessed properties similar to that of the final product, Sterne developed its technology so it could deposit filaments of 100% UV-cured silicone. It’s definitely not easy to 3D print with silicone, due to properties that make it unable to be heated and extruded in the same way that typical thermoplastic materials can be, but companies like Sterne, Wacker Chemie, and Fripp Design Research have been making great strides over the last few years.

Over the last two years, Sterne, which has over 20 years of experience in the silicone industry, has been working hard to refine its 3D printing silicone technology, so it can be a viable alternative option for customers looking to meet their technical needs. Now the company is bringing its SiO-shaping 3D silicone printing method to COMPAMED 2018, a trade fair for medical suppliers and manufacturers which begins in a little over a week in Düsseldorf, Germany.

According to a release by the company, “Sterne is able to manufacture little to medium series on projects dedicated to 3D printing. An approved solution for pieces with a need situated between molding and extrusion technics, on specific applications both medical and short term implantable. Now, it is only in one step that devices with complex and atypical forms can be produced. A research and development department composed of 3D specialists and engineers, go with clients on project development and monitoring, perpetuating new concepts and ideas. A quick manufacturing on competitive deadlines since no design or validation of tools is necessary.”

The company’s SiO 3D silicone printing has been further refined since it was first introduced. In 2016, it promised a minimum 3D print layer height of 0.25 mm, but can now achieve a minimum of 0.1 mm (100 microns). Its SiO-Shaping 1601 silicone 3D printer offers a maximum print volume of 205 x 200 x 100 mm, along with hardness from 30 to 60 Shores A.

Sterne’s silicone 3D printing can help all of its customers with their fast prototyping needs. But its specialty is manufacturing thin, accurate silicone products for the medical sector that meet the necessary aesthetic and technical needs.

“Whether High Consistency Silicone Rubber (HCR) or Liquid Silicone Rubber (LSR), Sterne masters a large range of manufacturing process such as extrusion, molding, making, over-molding inside ISO 6, ISO 7 and ISO 8 cleanrooms,” the company’s release states.

In addition, Sterne’s SiO silicone 3D printing also offers a full panel of colors, including phosphorescent, translucent, and opaque, which is available for colors like red, yellow, black, and green. However, these colors are only available for materials that meet the necessary quality requirements according to the FDA or USP class VI medical grade.

You can see the company’s silicone 3D printing prowess for yourself at COMPAMED from November 12-15 in the Düsseldorf exhibition center. To rediscover, or see for the first time, Sterne’s range of products for the medical sector, visit the company at Stand L02 in Hall 08b.

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