Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Breaking point: LSU professor discovers method to determine when metals reach end of life

14.01.2011
We live in a world almost completely dependent upon machinery. Since the creation of the simple wheel, humans have found ways to increase quality of life and advance scientific knowledge using these devices.

Though the prevalence of machinery has allowed us to build bigger, travel faster and create more quickly with complexity increasing as science advances, our dependence upon them has limitations. Everything that moves can and will break, especially metals under strain. And when they fail, the consequences can be catastrophic. LSU's Michael Khonsari has developed and proven a novel method to avoid the danger that comes with reaching the breaking point.

Under the direction of Khonsari, Dow Chemical Endowed Chair in Rotating Machinery, the Center for Rotating Machinery in LSU's College of Engineering has developed a method to determine when metals under repeated back and forth stress will reach their breaking point. This discovery has the potential to save industry millions of dollars – and also save lives.

"It has far-reaching implications … this isn't going to impact just one industry or field," said Khonsari. "Machines impact our everyday lives, from automobiles to aviation, and breakdowns can cause immense complications. We're working to minimize those while maximizing efficient output."

The point at which materials reach a breaking point is a major concern. Chemical plants, for instance, rely on vast amounts of machinery to run efficiently and safely at all times. An emergency shutdown of just one piece of machinery could cost millions of dollars at best; at worst, it can cost lives.

"We have determined that most metals respond similarly when subjected to external cyclic stress that causes fatigue. While any kind of repetitive stress – bending, torsion, tension and compression – results in an increase in temperature, the moments before breakdown are precipitated by a sudden, drastic rise in temperature," said Khonsari. "What's more, we've determined that as a metal degrades, the amount of disorder generated within it keeps rising to a maximum value just before it fractures. And this maximum value happens to be a unique property of the metal. This discovery means we can anticipate the moment of failure and shut down before that moment arrives."

To reach these answers, Khonsari and his group had to go back to some basic questions and formulate their research in a totally new way.

"We had to ask ourselves those very fundamental questions. What is fatigue? What is wear? How to we characterize fatigue and wear? And is there a unifying principle behind all of these phenomena that basically cause degradation in a system? We had to start from the ground up."

He and his research team found that degradation results in disorder within a material and increases its entropy, a thermodynamic principle manifesting itself in an increase in temperature. They hypothesized that, at the moment of material failure, the total accumulated entropy is constant and independent of frequency, load or specimen size. The research was originally published in the Proceedings of the Royal Society of Mathematical, Physical & Engineering Sciences.

"The science base that underlies modeling and analysis of machine and structure reliability has remained substantially unchanged for decades. And unfortunately, a significant gap exists between available technology and science to capture degradation of machinery and provide early failure prediction," said Khonsari. "Fortunately, we were able to make significant strides toward closing that gap."

Using infrared cameras and cutting-edge computer technology, they ran tests analyzing bending and torsional stress of common metals such as aluminum and stainless steel. The thorough testing proved their hypothesis – the total accumulated entropy before fracture occurred was constant. In other words, it is a metal property. This led them to their next line of questioning.

"We essentially found an end to the life of certain materials in which you can monitor entropy accumulation to avoid catastrophic failure, so why not use this information to automatically stop the machine when the system reaches, say, 90 percent of its life?" said Khonsari. "Computerized monitoring systems and the algorithms and signal relay capable of doing so were all developed here at the Center for Rotating Machinery at LSU. Naturally, there was a process of trial and error, but it's all been tested and verified now. It's the real thing."

Because of the LSU College of Engineering's stature in industry in Louisiana and around the globe, Khonsari is confident that this research won't simply sit unused in a lab. It meets current industry needs. He knows, because the college meets with industry representatives on a regular basis to determine just that.

"The LSU College of Engineering's industry connections have been a huge help to us during every stage of this process," said Khonsari. "Research and development is not a quick process. There are many factors, including safety, that have to be considered and tested. Once we have tested it at LSU and feel confident that the product is up to par, it's a great advantage to then use it on a preliminary basis in industry situations so we can see how it performs outside the laboratory environment."

Khonsari submitted invention disclosures describing the technology to the LSU Office of Intellectual Property, Commercialization and Development and two patents are pending. The office is currently investigating licensing and commercialization opportunities.

"Before our venture into this area, research relating to fatigue was slow and incremental," said Khonsari. "Now, we're looking at potentially transformative new ideas. There are possibilities for this to be applied in nearly every aspect of our lives. Imagine being able to know before an airplane element breaks, a helicopter blade cracks or the brakes in a car fail. Things like this are possible through future applications of our work. And it all happened at LSU by a team of researchers at the Center for Rotating Machinery."

More news and information can be found on LSU's home page at www.lsu.edu

Ashley Berthelot | EurekAlert!
Further information:
http://www.lsu.edu

Further reports about: Breaking Waves LSU Rotating chemical engineering monitoring system

More articles from Materials Sciences:

nachricht Move over, Superman! NIST method sees through concrete to detect early-stage corrosion
27.04.2017 | National Institute of Standards and Technology (NIST)

nachricht Control of molecular motion by metal-plated 3-D printed plastic pieces
27.04.2017 | Ecole Polytechnique Fédérale de Lausanne

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>