Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

MIT researchers develop new ultralight, ultrastiff 3D printed materials

20.06.2014

Imagine a material with the same weight and density as aerogel -- a material so light it's called 'frozen smoke' -- but with 10,000 times more stiffness. This material could have a profound impact on the aerospace and automotive industries as well as other applications where lightweight, high-stiffness and high-strength materials are needed.

Lawrence Livermore National Laboratory (LLNL) and Massachusetts Institute of Technology (MIT) researchers have developed a material with these properties using additive micro-manufacturing processes. The research team's findings are published in a June 20 article in the journal Science.


Lawrence Livermore Engineer Xiaoyu "Rayne" Zheng -- lead author of the Science article -- studies a macroscale version of the unit cell, which constitutes the ultralight, ultrastiff material. Photos by Julie Russell/LLNL.

Titled "Ultralight, Ultrastiff Mechanical Metamaterials," the article describes the team's development of micro-architected metamaterials -- artificial materials with properties not found in nature -- that maintain a nearly constant stiffness per unit mass density, even at ultralow density. Materials with these properties could someday be used to develop parts and components for aircraft, automobiles and space vehicles.

Most lightweight cellular materials have mechanical properties that degrade substantially with reduced density because their structural elements are more likely to bend under applied load. The team's metamaterials, however, exhibit ultrastiff properties across more than three orders of magnitude in density.

"These lightweight materials can withstand a load of at least 160,000 times their own weight," said LLNL Engineer Xiaoyu "Rayne" Zheng, lead author of the Science article. "The key to this ultrahigh stiffness is that all the micro-structural elements in this material are designed to be over constrained and do not bend under applied load."

The observed high stiffness is shown to be true with multiple constituent materials such as polymers, metals and ceramics, according to the research team's findings.

"Our micro-architected materials have properties that are governed by their geometric layout at the microscale, as opposed to chemical composition," said LLNL Engineer Chris Spadaccini, corresponding author of the article, who led the joint research team. "We fabricated these materials with projection micro-stereolithography."

This additive micro-manufacturing process involves using a micro-mirror display chip to create high-fidelity 3D parts one layer at a time from photosensitive feedstock materials. It allows the team to rapidly generate materials with complex 3D micro-scale geometries that are otherwise challenging or in some cases, impossible to fabricate.

"Now we can print a stiff and resilient material using a desktop machine," said MIT professor and key collaborator Nicholas Fang. "This allows us to rapidly make many sample pieces and see how they behave mechanically."

The team was able to build microlattices out of polymers, metals and ceramics.

For example, they used polymer as a template to fabricate the microlattices, which were then coated with a thin-film of metal ranging from 200 to 500 nanometers thick. The polymer core was then thermally removed, leaving a hollow-tube metal strut, resulting in ultralight weight metal lattice materials.

"We have fabricated an extreme, lightweight material by making these thin-film hollow tubes," said Spadaccini, who also leads LLNL's Center for Engineered Materials, Manufacturing and Optimization. "But it was all enabled by the original polymer template structure."

The team repeated the process with polymer mircolattices, but instead of coating it with metal, ceramic was used to produce a thin-film coating about 50 nanometers thick. The density of this ceramic micro-architected material is similar to aerogel.

"It's among the lightest materials in the world," Spadaccini said. "However, because of its micro-architected layout, it performs with four orders of magnitude higher stiffness than aerogel at a comparable density."

Lastly, the team produced a third ultrastiff micro-architected material using a slightly different process. They loaded a polymer with ceramic nanoparticles to build a polymer-ceramic hybrid microlattice. The polymer was removed thermally, allowing the ceramic particles to densify into a solid. The new solid ceramic material also showed similar strength and stiffness properties.

"We used our additive micro-manufacturing techniques to fabricate mechanical metameterials with unprecedented combinations of properties using multiple base material constituents - polymers, metals, and ceramics," Spadaccini said.

The LLNL-MIT teams' new materials are 100 times stiffer than other ultra-lightweight lattice materials previously reported in academic journals.

In addition to Spadaccini, Fang and Zheng, the LLNL-MIT research team consisted of LLNL researchers (Todd Weisgraber; Maxim Shusteff; Joshua Deotte; Eric Duoss; Joshua Kuntz; Monika Biener; Julie Jackson; and Sergei Kucheyev); and MIT researchers (Howon Lee and Qi "Kevin" Ge).

The Department of Defense's Defense Advanced Research Projects Agency (DARPA) and Lawrence Livermore's Laboratory Directed Research and Development (LDRD) program funded the team's research.

Founded in 1952, Lawrence Livermore National Laboratory provides solutions to our nation's most important national security challenges through innovative science, engineering and technology. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.

Ken Ma | Eurek Alert!
Further information:
https://www.llnl.gov/news/newsreleases/2014/Jun/NR-14-06-06.html#.U6QNl2GKDct

Further reports about: LLNL MIT Security coating materials metamaterials nanometers properties stiffness thin-film weight

More articles from Materials Sciences:

nachricht Controlling phase changes in solids
29.07.2015 | ICFO-The Institute of Photonic Sciences

nachricht Smart Hydrogel Coating Creates “Stick-slip” Control of Capillary Action
28.07.2015 | Georgia Institute of Technology

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Quantum Matter Stuck in Unrest

Using ultracold atoms trapped in light crystals, scientists from the MPQ, LMU, and the Weizmann Institute observe a novel state of matter that never thermalizes.

What happens if one mixes cold and hot water? After some initial dynamics, one is left with lukewarm water—the system has thermalized to a new thermal...

Im Focus: On the crest of the wave: Electronics on a time scale shorter than a cycle of light

Physicists from Regensburg and Marburg, Germany have succeeded in taking a slow-motion movie of speeding electrons in a solid driven by a strong light wave. In the process, they have unraveled a novel quantum phenomenon, which will be reported in the forthcoming edition of Nature.

The advent of ever faster electronics featuring clock rates up to the multiple-gigahertz range has revolutionized our day-to-day life. Researchers and...

Im Focus: Superfast fluorescence sets new speed record

Plasmonic device has speed and efficiency to serve optical computers

Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.

Im Focus: Unlocking the rice immune system

Joint BioEnergy Institute study identifies bacterial protein that is key to protecting rice against bacterial blight

A bacterial signal that when recognized by rice plants enables the plants to resist a devastating blight disease has been identified by a multi-national team...

Im Focus: Smarter window materials can control light and energy

Researchers in the Cockrell School of Engineering at The University of Texas at Austin are one step closer to delivering smart windows with a new level of energy efficiency, engineering materials that allow windows to reveal light without transferring heat and, conversely, to block light while allowing heat transmission, as described in two new research papers.

By allowing indoor occupants to more precisely control the energy and sunlight passing through a window, the new materials could significantly reduce costs for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Euro Bio-inspired - International Conference and Exhibition on Bio-inspired Materials

23.07.2015 | Event News

Clash of Realities – International Conference on the Art, Technology and Theory of Digital Games

10.07.2015 | Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

 
Latest News

Tool making and additive technology exhibition: Fraunhofer IPT at Formnext

31.07.2015 | Trade Fair News

First Siemens-built Thameslink train arrives in London

31.07.2015 | Transportation and Logistics

California 'rain debt' equal to average full year of precipitation

31.07.2015 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>