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Seeking info for science fair project about marine corrosion

i am in 6th grade doing a science fair project about marine corrosion.....corrosion blockers, etc. I want this to be a 5 year project, that I can grow with please mail to me any written literature you have on this topic. is their anyone....whether technical support, chemical, or environmental people that would be willing to be a "mentor" for me, incase I have questions I have to do a written report to go along with my project so if you could send info to the above address asap I would appreciate it thanks Brett j.

Brett J. [last name deleted for privacy by Editor]
-Jacksonville, Florida
2000

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2000

Poor old Brett! No reply for a coon's age (whatever that means).

Brett, as you know (or should know), that thar ocean consists of water and NaCl or salt.

This mixture, an alkaline, normally affects most metals, i.e. in plain English it attacks them. This even includes stainless steel and most plated products.

What you want to do is to go the library, speak to the chief librarian and say you want to get hold of some data on the acid resistance of metals (i.e., corrosion resistance is a better word).

The next step is to get hold of/beg or borrow a catalogue from a major plastics fabricator or distributor as some of them also show most metals as well as plastic resistance charts. There is one U.S. manufacturer of PVC valves and, I believe, fittings but whose name escapes me. They used to be called CABOT.

PLASTICS ... I guess that salt water will not attack/affect any plastic which is why many smaller vessels have been made from fibreglass ... it being the fibreglass resin that protects the laminate and they range from the 'ordinary' isothallic' to the more expensive (and more corrosion resistant) special resins that heavy industry uses to fight severe corrosion.

Lastly ... what might interest you marinewise is that were you hatching fish eggs at school and the water inlet piping was copper, the fingerlings would die. The solution? Use PVC. This is an enormously inert material.

Sorry for the delay. Hope it helps.

Cheers !

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

Brett and Freeman. Because my career has been with a company that makes copper alloys used for marine and petrochemical applications, I feel compelled to mention that copper and it's alloys (with other elements like aluminum, nickel, tin and/or silicon), have been the mainstay materials of choice to resist marine corrosion for thousands of years. Even the Phoenicians and Vikings were aware of their benefits. I will concede that plastics have their places, where metals do not work. While it is true that traces of copper in a marine-like environment of an aquarium is toxic, this is also what allows a fishing boat made of cupronickel plate, for example, to go out to sea for years, and not accumulate the marine crustaceans that stick to fiberglass and steel ships, causing them to be drydocked regularly, for cleaning (unless protected by paint coatings containing copper).

One lesson to be learned is that all man-made materials have specific uses that are ideal, others that are only marginally OK, and still others that uninformed people try, and when these fail, they condemn the materials, rather than that they failed to evaluate the environment of the application properly.

Another lesson is that a material's purchase price is only part of the cost to a material's life cycle. How well it resists wear and corrosion, and how easy it will be to recycle it at the end of it's useful life, are equally important considerations. Good luck in your research, just keep an open mind. I suggest you check "The Copper Page" website for additional information.

W. Carl Erickson
- Rome, New York, USA
2001

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Brett - The American Society for Testing and Materials (www.astm.org for ASTM standards) recently put on a symposium on Corrosion in Marine Environments and published a book of all the technical papers presented. You can obtain this book from ASTM at their web site. It will include the most up-to-date information. Good luck.

Cindy Meade
- Sylvania, Ohio, USA
2001