Featured Research

from universities, journals, and other organizations

X-ray diffraction technique 'maps' strain, crack propagation in metallic tubing

Date:
January 22, 2014
Source:
NACE International
Summary:
A team of researchers exploring the intergranular stress corrosion cracking of a type of metallic tubing used within nuclear power plants has developed a technique to both map and predict its propagation.

mage caption: This series of images show the x-ray maps of a crack along the surface of Alloy 500 tubing. In (a), the absorption map shows parts of the physical crack; (b) shows the grain orientations along the crack; (c) shows compressive stresses in blue as a result of the crack opening; (d) shows the crack's propagation path on the tubing via scanning electron micrograph, along with a "trench" created by ion beam for easier imaging of a crack cross section; (e) shows the crack opening.
Credit: University of Western Ontario

A team of researchers exploring the intergranular stress corrosion cracking of a type of metallic tubing used within nuclear power plants has developed a technique to both map and predict its propagation.

Related Articles


Metallic tubing plays a key role in transporting water coolant to steam generators within nuclear power plants. But for reasons that remain elusive, in this application, Alloy 600, a high-strength nickel-based alloy widely used and considered robust in other high-performance situations, is susceptible to costly failure caused by intergranular stress corrosion cracking.

A team of researchers delved into this longstanding technical issue by using an x-ray diffraction technique to measure structural changes within microscopic areas on the metallic tubing, which they describe in a paper in CORROSION journal.

"Failures of Alloy 600 are preceded by mechanical strains, but the location of this type of strain is often a tiny area only a few microns wide, which has been mechanically damaged by a physical process like a micro scratch or a chemical process such as rapid local corrosion," explains Stewart McIntyre, co-author of the paper and an emeritus professor in the Department of Chemistry at the University of Western Ontario in London, Canada.

It's important to "identify the very tiny areas on samples that are under local tensile stresses -- because these stresses can pull a material apart at the boundary between two metal grains," McIntyre says.

To zero in on these areas under local tensile stresses, McIntyre and colleagues turned to a very small and coherent x-ray beam of the sort produced in synchrotrons, such as the Advanced Light Source at Lawrence Berkeley National Laboratory.

"With such facilities we can 'map' the location of strains to determine whether their direction is likely to result in crack propagation in the future," says McIntyre.

Next up? The researchers plan to study the effects of external stresses of different magnitudes imposed on boiler tubing made from Alloy 600, as well as its new replacement, Alloy 690.


Story Source:

The above story is based on materials provided by NACE International. Note: Materials may be edited for content and length.


Journal Reference:

  1. N.S. McIntyre, J. Ulaganathan, T. Simpson, J. Qin, N. Sherry, M. Bauer, A. G. Carcea, R. C. Newman, M. Kunz, N. Tamura. Mapping of Microscopic Strain Distributions in an Alloy 600 C-Ring after Application of Hoop Stresses and Stress Corrosion Cracking. Corrosion, 2013; 130806113143002 DOI: 10.5006/1006

Cite This Page:

NACE International. "X-ray diffraction technique 'maps' strain, crack propagation in metallic tubing." ScienceDaily. ScienceDaily, 22 January 2014. <www.sciencedaily.com/releases/2014/01/140122134319.htm>.
NACE International. (2014, January 22). X-ray diffraction technique 'maps' strain, crack propagation in metallic tubing. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2014/01/140122134319.htm
NACE International. "X-ray diffraction technique 'maps' strain, crack propagation in metallic tubing." ScienceDaily. www.sciencedaily.com/releases/2014/01/140122134319.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins