Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Components based on nature's example

06.10.2011
The exceptional strength of certain biological materials is due principally to their complex structure.

Long bones, for instance, consist of a compact, solid outer casing filled with spongy tissue, which makes them particularly strong and resilient. Researchers from the Fraunhofer Institutes for Mechanics of Materials IWM and for Environmental, Safety and Energy Technology UMSICHT are collaborating on a project entitled "Bionic Manufacturing", which aims to develop products that are lightweight but strong and economic in their use of materials – imitating the perfected structures found in nature.


The picture on the left shows a lightweight structure made of polyamide inspired by bionic principles. The picture on the right shows its detailed simulation on the computer. Credit: Fraunhofer IWM

The IWM scientists in Freiburg have taken on the task of identifying the best internal structures for manufactured components. "We have set ourselves the challenge of working as efficiently as nature: The finished component must not weigh more than necessary and yet still be able to perform its mechanical function reliably," explains Dr. Raimund Jaeger of IWM. This approach can be combined with a high degree of creative freedom: "Such components can be used to produce consumer goods with a high aesthetic value, such as designer chairs," adds Jaeger. And if by chance one of these bionically designed objects should break as the result of excessive loading, it will do so in a benign way – collapsing smoothly in localized areas rather than shattering into sharp splinters.

Whereas natural materials have evolved over numerous generations to reach the level of perfection we see today, engineers and product designers have to work much faster. The Freiburg research team has therefore developed a new design method. They start by constructing a virtual model of the future workpiece on the computer, filling out its contours with almost identical, cube-shaped, elementary cells. If the numerical simulation reveals that the grid structure does not satisfy requirements, the cell walls (trabecular microstructure) are refined accordingly. "We make them thicker if they are too weak and thinner if they need to be more pliable, or align them with the force lines along which the load is distributed," explains Jaeger. This method enables many different shapes to be designed around an inner cell structure that can then be evaluated and optimized using the simulation tool. To complement the simulations, the researchers carry out tests on real-life components to verify the structure's mechanical properties.

Jaeger reports that the method has worked very well every time they have used it to design any type of workpiece based on two-dimensional templates that can be pulled into the desired shape using the computer simulation. The same applies to components with a relatively regular shape. Despite their light weight, all of these components are very strong and resilient and capable of absorbing even substantial shocks. According to the scientists, they have potential applications wherever there is a need for products that combine a high level of mechanical stability and aesthetic appearance with low weight – for example medical orthopedic devices or anatomically formed body protectors such as lumbar support belts for skiers.

Fraunhofer UMSICHT is responsible for the technical implementation of the bionic design principles. The solution chosen by the project managers in Oberhausen involves the use of additive manufacturing techniques – in this case selective laser sintering of polymer materials. This technique enables workpieces to be fabricated by laying down successive layers of a fine polyamide powder, which are fused together in the desired configuration using a focused laser beam. It is the ideal method for creating complex internal structures and, at a later stage, components with a distributed pattern of material properties, which experts refer to as functionally graded materials. The resulting structures are similar to those observed in nature.

Raimund Jaeger | EurekAlert!
Further information:
http://www.iwm.fraunhofer.de

More articles from Materials Sciences:

nachricht Physics, photosynthesis and solar cells
01.12.2016 | University of California - Riverside

nachricht New process produces hydrogen at much lower temperature
01.12.2016 | Waseda University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>