Material Science News and Discussions

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Scientists spin naturalistic silk from artificial spider gland
https://phys.org/news/2024-01-scientist ... pider.html
by RIKEN

Researchers have succeeded in creating a device that spins artificial spider silk that closely matches what spiders naturally produce. The artificial silk gland was able to re-create the complex molecular structure of silk by mimicking the various chemical and physical changes that naturally occur in a spider's silk gland.

This eco-friendly innovation is a big step towards sustainability and could impact several industries. The study, led by Keiji Numata at the RIKEN Center for Sustainable Resource Science in Japan, along with colleagues from the RIKEN Pioneering Research Cluster, was published in the journal Nature Communications.

Famous for its strength, flexibility, and light weight, spider silk has a tensile strength that is comparable to steel of the same diameter, and a strength-to-weight ratio that is unparalleled. Added to that, it's biocompatible, meaning that it can be used in medical applications, as well as biodegradable. So why isn't everything made from spider silk? Large-scale harvesting of silk from spiders has proven impractical for several reasons, leaving it up to scientists to develop a way to produce it in the laboratory.

Spider silk is a biopolymer fiber made from large proteins with highly repetitive sequences, called spidroins. Within the silk fibers are molecular substructures called beta sheets, which must be aligned properly for the silk fibers to have their unique mechanical properties. Re-creating this complex molecular architecture has confounded scientists for years. Rather than trying to devise the process from scratch, RIKEN scientists took a biomimicry approach.

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Scientists announce breakthrough in hypersonic heat shield
https://techxplore.com/news/2024-01-sci ... hield.html
by Peter Grad , Tech Xplore

In a giant leap for future hypersonic flight, Chinese scientists have turned to multi-scale technology to develop a revolutionary new material that has achieved record high marks in tests for vital strength and thermal insulation properties.

The scientists say their porous ceramic creation opens the door to wider exploration in the fields of aerospace, chemical engineering and energy transfer and production.

"For the first time, it is reported a multi-scale structure design and fast fabrication of … high-entropy ceramics via an ultrafast high-temperature synthesis technique that can lead to exceptional mechanical load-bearing capability and high thermal insulation performance," the researchers said in a paper published Jan. 2 in the journal Advanced Materials.

Scientists have long faced challenges in developing strong, lightweight materials boasting low-thermal conductivity that are critical, especially for hypersonic travel. Ceramic materials offer promise because they exhibit low thermal conductivity, high melting points and corrosion resistance, and they are also non-combustible.

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Airborne infection risk plummets in face of metal nanoparticle spray
By Michael Franco
January 25, 2024
https://newatlas.com/materials/airborne ... cle-spray/

As recent history proves, airborne respiratory infections are not to be trifled with. Now, a new sprayable coating applied to standard air filters might give us a leg up in the war against the pathogens that cause these diseases.

Measles. Influenza. SARS. MERS. Pneumonia. Think of a major infectious disease, and the chances are that it is spread by airborne pathogens. Currently, COVID-19 and TB are the world's deadliest infectious diseases, and both are transmitted through the air. So when it comes to tamping down the risk of disease spreading through populations, developing solutions that can knock infectious bugs out of the air is paramount.

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Graphene replaces sand to make lighter, stronger concrete
By Michael Irving
January 28, 2024

https://phys.org/news/2024-01-sea-metha ... lands.html
When you think of resources we’re running out of, sand might not be high on your list, but it’s up there thanks to our high demand for concrete. Scientists at Rice University have now shown that substituting graphene can not only save sand, but makes concrete lighter, stronger and tougher.

Despite being a sheet of carbon atoms just one atom thick, graphene has a reputation for being incredibly strong. As such, it’s no surprise that this 'wonder material' has been mixed into concrete before, usually to make it stronger and more durable. But that usually involves just adding graphene to the recipe – for the new study, the Rice team wanted to replace sand completely.

Concrete is made of three main ingredients: water, an aggregate like sand, and cement to bind it all together. Sand is the largest component by volume, and given modern humanity’s insatiable appetite for concrete, sand mining is increasing. Not only is this process destructive, but it risks running out of sources.

The research comes from the lab of Rice University chemist James Tour, whose team has been making graphene for years using a technique they developed called flash Joule heating. Essentially, a carbon-rich base material is quickly superheated with a zap of electricity, converting it into graphene flakes. In this case, the base material was metallurgical coke, a fuel source created from coal.

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A type of plastic that can be shape-shifted using tempering
https://phys.org/news/2024-02-plastic-s ... ering.html
by Bob Yirka , Phys.org

A team of molecular engineers have developed a type of plastic that can be shape-shifted using tempering. In their paper published in the journal Science the team, from the University of Chicago, with a colleagues from the US DEVCOM Army Research Laboratory, Aberdeen Proving Ground, the National Institutes of Standards and Technology and the NASA Glenn Research Center, describe how they made their plastic and how well it was able to shape shift when they applied various types of tempering.

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Researchers create green steel from toxic red mud in 10 minutes
By Paul McClure
February 06, 2024

Researchers have devised an economically viable way of reducing the environmental impact of both the steel and aluminum industries by using hydrogen to melt down the toxic red mud left over from aluminum production to produce green steel in around 10 minutes.

The aluminum industry produces around 198 million tons (180 million tonnes) of bauxite residue – ‘red mud’ – yearly, which is extremely corrosive because it has high alkalinity and is rich in toxic heavy metals. In countries such as Australia, China and Brazil, the leftover red mud is usually disposed of in gigantic landfills, with high processing costs. The steel industry is equally environmentally damaging, responsible for 8% of global carbon dioxide emissions. Yet, the demand for steel and aluminum is forecast to increase by up to 60% by 2050.

https://newatlas.com/materials/toxic-ba ... een-steel/

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Surprise physics in insulating material offer path for faster tech
https://phys.org/news/2024-02-physics-i ... aster.html
by Syl Kacapyr, Cornell University

Researchers led by Cornell have discovered an unusual phenomenon in a metal-insulating material, providing valuable insights for the design of materials with new properties by way of faster switching between states of matter.

Mott insulators are a family of materials with unique electronic properties, including ones that can be manipulated by stimuli such as light. The origin of the unique properties is not fully understood, partly due to the challenging task of imaging the material's nanostructures in real-space and capturing how these structures undergo phase changes in as fast as a trillionth of a second.

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BREKTHROUGH : Non-Fading Structural Color For Airplane Paint With 10% of the Weight
February 10, 2024 by Brian Wang

A new way of creating color uses the scattering of light of specific wavelengths around tiny, almost perfectly round silicon crystals. This Kobe University development enables non-fading structural colors that do not depend on the viewing angle and can be printed. The material has a low environmental and biological impact and can be applied extremely thinly, promising significant weight improvements over conventional paints.

Above -The nanospheres in a methanol suspension have different colors than when applied to a surface as a monolayer. The Kobe University researchers explain, “This is due to the multiple scattering, i.e., blue light subsides during consecutive scattering by absorption, while red light survives.” © FUJII Minoru (CC BY)

https://www.nextbigfuture.com/2024/02/b ... eight.html

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Polymer-based tunable optical components allow for metasurfaces that can switched with light
https://phys.org/news/2024-02-polymer-b ... nents.html
by Marco Körner, Friedrich Schiller University of Jena

A material coating, whose light refraction properties can be precisely switched between different states, has been developed by an interdisciplinary research team from the Chemistry and Physics departments at the University of Jena. The team, led by Felix Schacher, Sarah Walden, Purushottam Poudel, and Isabelle Staude, combined polymers that react to light with so-called metasurfaces.

This innovation has led to the creation of new optical components that could potentially be used in signal processing. Their findings have now been published in the journal ACS Nano.

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3D-printed titanium lattice is 50% stronger than WE54 aerospace alloy
By Loz Blain
February 26, 2024
https://newatlas.com/materials/3d-print ... tice-rmit/

A new type of 3D-printed lattice structure has surprised researchers with its strength and light weight. It uses two different lattice structures merged together to eliminate the weak points normally found in these complex shapes.

RMIT researchers in Melbourne, Australia, took hollow-strut lattice designs as a starting point, inspired by hollow-stemmed water lilies and organ pipe coral, and then looked at ways to reduce the high stress concentrations created at the join points.

“Ideally, the stress in all complex cellular materials should be evenly spread,” said Distinguished Professor Ma Qian, lead author on a new study. “However, for most topologies, it is common for less than half of the material to mainly bear the compressive load, while the larger volume of material is structurally insignificant.”

The researchers reinforced the tubular lattice by overlaying a second lattice over the top, adding a thin X-shaped cross-section running through the tubes and joints that distributes load much more evenly in compression testing.