Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > 'Buildings' in human bone may hold key to stronger 3D-printed lightweight structures

Engineers designed a material with the same amount of rod- and plate-like structures as human trabeculae and arranged them in a periodic pattern, presenting a new way to strengthen lightweight 3D-printed structures.

CREDIT
Purdue University photo/Pablo Zavattieri
Engineers designed a material with the same amount of rod- and plate-like structures as human trabeculae and arranged them in a periodic pattern, presenting a new way to strengthen lightweight 3D-printed structures. CREDIT Purdue University photo/Pablo Zavattieri

Abstract:
Bone-Inspired Microarchitectured Materials with Enhanced Fatigue Life

Ashley M. Torres,1 Adwait A. Trikanad,2 Cameron A. Aubin,1 Floor M. Lambers,1 Marysol Luna,1 Clare M. Rimnac,3 Pablo Zavattieri,2 Christopher J. Hernandez,1,4

1Cornell University, Ithaca, NY, USA

2Purdue University, West Lafayette, IN, USA

3Case Western Reserve University, Cleveland, OH, USA

4Hospital for Special Surgery, New York, NY, USA

DOI: 10.1073/pnas.1905814116

Microarchitectured materials achieve superior mechanical properties through geometry rather than composition. Although ultralightweight microarchitectured materials can have high stiffness and strength, application to durable devices will require sufficient service life under cyclic loading. Naturally occurring materials provide useful models for high-performance materials. Here, we show that in cancellous bone, a naturally occurring lightweight microarchitectured material, resistance to fatigue failure is sensitive to a microarchitectural trait that has negligible effects on stiffness and strength--the proportion of material oriented transverse to applied loads. Using models generated with additive manufacturing, we show that small increases in the thickness of elements oriented transverse to loading can increase fatigue life by 10 to 100 times, far exceeding what is expected from the associated change in density. Transversely oriented struts enhance resistance to fatigue by acting as sacrificial elements. We show that this mechanism is also present in synthetic microlattice structures, where fatigue life can be altered by 5 to 9 times with only negligible changes in density and stiffness. The effects of microstructure on fatigue life in cancellous bone and lattice structures are described empirically by normalizing stress in traditional stress vs. life (S-N) curves by ?ψ, where ψ is the proportion of material oriented transverse to load. The mechanical performance of cancellous bone and microarchitectured materials is enhanced by aligning structural elements with expected loading; our findings demonstrate that this strategy comes at the cost of reduced fatigue life, with consequences to the use of microarchitectured materials in durable devices and to human health in the context of osteoporosis.

'Buildings' in human bone may hold key to stronger 3D-printed lightweight structures

West Lafayette, IN | Posted on December 6th, 2019

What do bones and 3D-printed buildings have in common? They both have columns and beams on the inside that determine how long they last.

Now, the discovery of how a "beam" in human bone material handles a lifetime's worth of wear and tear could translate to the development of 3D-printed lightweight materials that last long enough for more practical use in buildings, aircraft and other structures.

A team of researchers at Cornell University, Purdue University and Case Western Reserve University found that when they mimicked this beam and made it about 30% thicker, an artificial material could last up to 100 times longer.

"Bone is a building. It has these columns that carry most of the load and beams connecting the columns. We can learn from these materials to create more robust 3D-printed materials for buildings and other structures," said Pablo Zavattieri, a professor in Purdue's Lyles School of Civil Engineering.

Bones get their durability from a spongy structure called trabeculae, which is a network of interconnected vertical plate-like struts and horizontal rod-like struts acting as columns and beams. The denser the trabeculae, the more resilient the bone for everyday activities. But disease and age affect this density.

In a study published in the Proceedings of the National Academy of Sciences, the researchers found that even though the vertical struts contribute to a bone's stiffness and strength, it is actually the seemingly insignificant horizontal struts that increase the fatigue life of bone.

Christopher Hernandez's group at Cornell had suspected that horizontal strut structures were important for bone durability, contrary to commonly held beliefs in the field about trabeculae.

"When people age, they lose these horizontal struts first, increasing the likelihood that the bone will break from multiple cyclic loads," said Hernandez, a professor of mechanical, aerospace and biomedical engineering.

Studying these structures further could inform better ways to treat patients suffering from osteoporosis.

Meanwhile, 3D-printed houses and office spaces are making their way into the construction industry. While much faster and cheaper to produce than their traditional counterparts, even printed layers of cement would need to be strong enough to handle natural disasters - at least as well as today's homes.

That problem could be solved by carefully redesigning the internal structure, or "architecture," of the cement itself. Zavattieri's lab has been developing architected materials inspired by nature, enhancing their properties and making them more functional.

As part of an ongoing effort to incorporate nature's best strength tactics into these materials, Zavattieri's lab contributed to mechanical analysis simulations determining if horizontal struts might play a larger role in human bone than previously thought. They then designed 3D-printed polymers with architectures similar to trabeculae.

The simulations revealed that the horizontal struts were critical for extending the fatigue life of bone. A YouTube video is available at https://youtu.be/XK7NZMZ4YDs.

"When we ran simulations of the bone microstructure under cyclic loading, we were able to see that the strains would get concentrated in these horizontal struts, and by increasing the thickness of these horizontal struts, we were able to mitigate some of the observed strains," said Adwait Trikanad, a co-author on this work and civil engineering Ph.D. student at Purdue.

Applying loads to the bone-inspired 3D-printed polymers confirmed this finding. The thicker the horizontal struts, the longer the polymer would last as it took on load.

Because thickening the struts did not significantly increase the mass of the polymer, the researchers believe this design would be useful for creating more resilient lightweight materials.

"When something is lightweight, we can use less of it," Zavattieri said. "To create a stronger material without making it heavier would mean 3D-printed structures could be built in place and then transported. These insights on human bone could be an enabler for bringing more architected materials into the construction industry."

###

Other study authors include Ashley Torres, Cameron Aubin and Marysol Luna at Cornell and Clare Rimnac at Case Western Reserve University.

Hernandez and Zavattieri have been organizing and leading mentoring activities for students and young investigators as part of the Society of Hispanic Professional Engineers. The work was financially supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases and a National Science Foundation CAREER award for which Zavattieri is a recipient.

####

For more information, please click here

Contacts:
Kayla Wiles

765-494-2432

@PurdueUnivNews

Copyright © Purdue University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

RELATED JOURNAL ARTICLE:

Related News Press

News and information

The National Space Society Congratulates Blue Origin and Jeff Bezos for the Spectacular First Crewed Flight of the New Shepard: Well-Tested Suborbital Tourist Rocket Soars to 63 Miles; Opens New Frontiers July 21st, 2021

Unconventional superconductor acts the part of a promising quantum computing platform: If it looks like a duck, swims like a duck and quacks like a duck, then it probably is a duck. July 16th, 2021

Unlocking efficient light-energy conversion with stable coordination nanosheets: Scientists design a high-performance, self-powered, UV photodetector using 2D nanosheets that show record photocurrent stability under air exposure July 16th, 2021

The virus trap: Hollow nano-objects made of DNA could trap viruses and render them harmless July 16th, 2021

Primers with graphene nanotubes offer a new solution for electrostatic painting of automotive parts July 16th, 2021

Videos/Movies

Scientists create rechargeable swimming microrobots using oil and water July 16th, 2021

Scientists take first snapshots of ultrafast switching in a quantum electronic device: They discover a short-lived state that could lead to faster and more energy-efficient computing devices July 16th, 2021

Rice lab peers inside 2D crystal synthesis: Simulations could help molecular engineers enhance creation of semiconducting nanomaterials June 11th, 2021

3D & 4D printing/Additive-manufacturing

New 3D-Bioprinter + Bioink Use Living Cells Straight From Culture Plate: Cell models mimicking natural tissue topography herald new era for biomedical research April 13th, 2021

Dynamic 3D printing process features a light-driven twist: Light provides freedom to control each layer and improves precision and speed February 4th, 2021

Russian scientists improve 3D printing technology for aerospace composites using oil waste November 27th, 2020

Materials scientists learn how to make liquid crystal shape-shift September 25th, 2020

Govt.-Legislation/Regulation/Funding/Policy

The virus trap: Hollow nano-objects made of DNA could trap viruses and render them harmless July 16th, 2021

Scientists create rechargeable swimming microrobots using oil and water July 16th, 2021

Scientists take first snapshots of ultrafast switching in a quantum electronic device: They discover a short-lived state that could lead to faster and more energy-efficient computing devices July 16th, 2021

Stress-free path to stress-free metallic films paves the way for next-gen circuitry: Optimized sputtering technique helps minimize stress in tungsten thin films July 4th, 2021

Possible Futures

The National Space Society Congratulates Blue Origin and Jeff Bezos for the Spectacular First Crewed Flight of the New Shepard: Well-Tested Suborbital Tourist Rocket Soars to 63 Miles; Opens New Frontiers July 21st, 2021

Scientists create rechargeable swimming microrobots using oil and water July 16th, 2021

Scientists take first snapshots of ultrafast switching in a quantum electronic device: They discover a short-lived state that could lead to faster and more energy-efficient computing devices July 16th, 2021

Researchers discover a new inorganic material with lowest thermal conductivity ever reported July 16th, 2021

Announcements

The National Space Society Congratulates Blue Origin and Jeff Bezos for the Spectacular First Crewed Flight of the New Shepard: Well-Tested Suborbital Tourist Rocket Soars to 63 Miles; Opens New Frontiers July 21st, 2021

Scientists create rechargeable swimming microrobots using oil and water July 16th, 2021

Scientists take first snapshots of ultrafast switching in a quantum electronic device: They discover a short-lived state that could lead to faster and more energy-efficient computing devices July 16th, 2021

Researchers discover a new inorganic material with lowest thermal conductivity ever reported July 16th, 2021

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

RUDN University chemists obtained an unusual planar nickel complex exhibiting magnetic properties July 16th, 2021

Repairs using light signals: FAU research group develops smart microparticle that identifies defective parts in electrical appliances July 16th, 2021

Scientists create rechargeable swimming microrobots using oil and water July 16th, 2021

Scientists take first snapshots of ultrafast switching in a quantum electronic device: They discover a short-lived state that could lead to faster and more energy-efficient computing devices July 16th, 2021

Construction

You're so vein: Scientists discover faster way to manufacture vascular materials May 14th, 2021

A quantum material-based diagnostic paint to sense problems before structural failure October 23rd, 2020

Discovery of disordered nanolayers in intermetallic alloys: Resolving alloys' strength-ductility trade-off and thermal instability July 24th, 2020

First measurement of electron energy distributions, could enable sustainable energy technologies June 5th, 2020

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project