Featured Research

from universities, journals, and other organizations

New self-healing coating for aluminum developed to replace cancer-causing product

Date:
October 22, 2012
Source:
University of Nevada, Reno
Summary:
Engineers have developed a new environmentally-friendly coating for aluminum to replace the carcinogenic chromate coatings used in aerospace applications. The chromate conversion coatings have been used for more than 50 years to protect aluminum from corrosion.

A University of Nevada, Reno research team has developed a new environmentally-friendly self-healing coating for aluminum that can be used for defense and aerospace applications. This image shows the formation of corrosion protective molybdate coating (blue) on aerospace aluminum alloy AA2024-T6. The process takes less than 8 minutes.
Credit: Professor Dev Chidambaram, University of Nevada, Reno.

A research team at the University of Nevada, Reno has developed a new environmentally-friendly coating for aluminum to replace the carcinogenic chromate coatings used in aerospace applications. The chromate conversion coatings have been used for more than 50 years to protect aluminum from corrosion.

Related Articles


The team presented their research last week at the international Pacific Rim Meeting on Electrochemical and Solid-State Science in Hawaii.

"It was well received at the conference," Dev Chidambaram, lead scientist and assistant professor of materials science and engineering at the University of Nevada, said. "There is no question that this will be able to replace the chromate-based coating. Even though the coating formulation is yet to be optimized, the coating has shown exceptional performance."

Attempts to replace chromate coatings with non-toxic coatings have been underway since the 1980s. The awareness on effects of chromates was brought to the forefront in 1993 by the real-life incident involving Erin Brokovich and depicted in the movie released in 2000 of the same name. Although the use of chromates for consumer and automotive applications has been banned, it is still in use by the defense and aerospace industries under various exemptions.

The carcinogenic coatings were exempted from the ban due to unavailability of suitable replacement combined with the high human and financial cost of failure from corrosion. The search for a suitable replacement has been elusive primarily due to one main characteristic of the coating referred to as "self-healing," the ability of the coating to heal itself after being damaged or scratched.

When scratched, the coating components from nearby sites migrate to the damaged region and re-protect the underlying alloy. A short video of the coating formation is on Chidambaram's website, www.electrochemical.org/ under the heading "Cool Videos."

Chidambaram's formulation performs comparably to the chromate formula in its ability for self-healing, which is important to the defense and aerospace industry. The coating can be applied to all aluminum products. The new formula creates an environmentally-benign molybdate-based coating that provides corrosion protection to aluminum, used for aircraft and spacecraft. These coatings, when damaged, will re-heal themselves.

The University of Nevada, Reno team developed and tested more than 300 coatings before arriving at this formulation. They used a complimentary suite of advanced surface analytical techniques such as Raman microspectroscopy, Fourier transform infrared spectroscopy, energy dispersive spectroscopy, secondary ion mass spectroscopy and X-ray photoelectron spectroscopy to conclusively prove the presence of molybdate in the scratched region. Further, using electrochemical testing, the team showed the coating re-protected itself via self-healing upon scratch test.

The team includes graduate student David Rodriquez, who conducted the extensive testing on the materials, and undergraduate aerospace engineering major at the University of Colorado, Boulder intern Roshan Misra, who began the project as a high school summer intern from Reno High School. The team is still working to optimize the coating formulation for even better protection.

"This has taken 14 years of work, continuing on work I did at the State University of New York at Stony Brook and the Brookhaven National Laboratory," Chidambaram said.


Story Source:

The above story is based on materials provided by University of Nevada, Reno. Note: Materials may be edited for content and length.


Cite This Page:

University of Nevada, Reno. "New self-healing coating for aluminum developed to replace cancer-causing product." ScienceDaily. ScienceDaily, 22 October 2012. <www.sciencedaily.com/releases/2012/10/121022145449.htm>.
University of Nevada, Reno. (2012, October 22). New self-healing coating for aluminum developed to replace cancer-causing product. ScienceDaily. Retrieved December 18, 2014 from www.sciencedaily.com/releases/2012/10/121022145449.htm
University of Nevada, Reno. "New self-healing coating for aluminum developed to replace cancer-causing product." ScienceDaily. www.sciencedaily.com/releases/2012/10/121022145449.htm (accessed December 18, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Thursday, December 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

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
3D Printed Cookies Just in Time for Christmas

3D Printed Cookies Just in Time for Christmas

Reuters - Innovations Video Online (Dec. 18, 2014) A tech company in Spain have combined technology with cuisine to develop the 'Foodini', a 3D printer designed to print the perfect cookie for Santa. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
How Sony Hopes To Make Any Glasses 'Smart'

How Sony Hopes To Make Any Glasses 'Smart'

Newsy (Dec. 17, 2014) Sony's glasses module attaches to the temples of various eye- and sunglasses to add a display and wireless connectivity. Video provided by Newsy
Powered by NewsLook.com
Los Angeles Police To Receive 7,000 Body Cameras

Los Angeles Police To Receive 7,000 Body Cameras

Newsy (Dec. 17, 2014) Los Angeles Mayor Eric Garcetti announced the cameras will be distributed starting Jan. 1. Video provided by Newsy
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