Corrosion in the News: June 17, 2019 Roundup
This week's stories take a look at several failures that were caused by corrosion and some new corrosion prevention improvements such as nanomaterials and coatings.
Welcome to the mid-June edition of our biweekly Corrosion News Roundup, where we give you what is breaking and relevant in the world of corrosion and the science behind preventing it. For this edition, we head to a couple municipalities to learn about corrosion concerns, one with a set of schools in Scotland and the other a city in Michigan with ambitious eco-friendly goals. We also showcase several corrosion inhibition improvements, such as new nanomaterial discoveries and new coatings. The aerospace industry is also a topic for this edition of the Corrosion News Roundup. Enjoy!
Nanomaterial Responsible for Corrosion on Steel Pipes
Scientists at Sandia National Labs and the Aramco Research Center in Boston have discovered a new form of corrosion in steel pipes that occurs at the nanomaterial level when two ferrite grains are combined at a junction with a grain of cementite. Both grain types are common in steel pipe. The corrosion occurs because at the boundary of these three grains, the ferrites, or pure iron grains, are allowed to release and leave an opening on the surface of the steel pipe. This in turn opens the door for subsequent types of corrosion. The combination of two ferrite grains and one cementite grain joining together occurs as a result of common steel pipe manufacturing processes. Scientists are currently looking into other ways to manufacture the steel pipe to prevent this combination from occurring.
Corrosion Causes Diminished Life Cycle of Airbus and Embraer Jets
The Airbus A220 and the Embraer E2 jet models have had a portion of their engine service life reduced due to unforeseen corrosion issues. Pratt and Whitney, the engine manufacturer, notified the airplane manufacturers of the issue recently after the corrosion was discovered. The corrosion occurs at the high-pressure compressor hub in some engines and could potentially result in cracking before the engine reaches its originally intended lifespan. Discussions about the exact measures to be taken will be ongoing as more investigations are performed.
Sherwin-Williams Announces New Coating
Sherwin-Williams, a multibillion dollar by revenue paint and coatings company, announced earlier this June that it will release a new coating for its architectural building product line. Powdura 4000 Anodite is the name for the proprietary powder coating blend. Specially formulated so that it gives the appearance of an anodized metal, it is initially available in 12 colors.
The appearance of anodized material is achieved through the use of mica pigments. Similar to actual anodized material, this coating is extremely resistant to harsh weather conditions. Since it is a powder coating and does not require an actual anodization process, Powdura 4000 Anodite can be applied to materials that are not typically anodized, such as steel.
Corrosion Causes Mercedes-Benz to Recall Vehicles
The German automaker Mercedes-Benz has decided to issue a recall for their Metris vans made in 2016-17 for 22 states in the United States as well as the District of Columbia; vans in Canada have also been included in the recall. The recall comes as a result of an investigation that found that aluminum bolts used to control steering in the vans could corrode when exposed to high amounts of saltwater and subsequently fracture. This in turn could cause loss of steering control and potentially an accident.
The states where the recall is occurring typically have large amounts of snow, and therefore, large amounts of road salt. Vehicles returned for the recall will be outfitted with bolts with improved corrosion resistance.
Corrosion Worries Cause Scrutiny in Scotish Schools
In Scotland, two schools in the County of Lanark are under scrutiny for not being on par with appropriate health standards. The concerns first arose when bluish water was found coming out of the water valves, which was caused by corroded copper.
An investigation is being conducted due to concern for the health of people attending and working at the school. This scrutiny is further augmented by the fact that the two schools in question were built on an old landfill and a previous industrial site. Some parents have begun to withdraw their students from the schools as a result of the findings. More investigation is needed to determine if there are additional reasons beyond the findings of corroded copper in the water to cause concern about other potential health code violations.
Corrosion-resistant Material Helps City Go Green
The city of Grand Rapids, Michigan has a “Going Green” goal of completely powering city buildings with renewable energy by the year 2025. One of the latest of its actions to achieve this goal is to build a biodigester. Biodigesters take organic material, such as unusable portions of produce and waste materials, and convert them into energy.
However, because of the risk associated with organic material and other types of waste corroding the biodigester, the biodigester must be made from corrosion-resistant materials. The biodigesters for the Grand Rapids application will incorporate stainless steels and other corrosion resistant materials in order to withstand the corrosive effects of the biological matter going into it. The use of these corrosion resistant materials will help the city move forward to achieve its environmentally conscious goals.