What Metals Rust the Fastest (Steel, Copper, Bronze)

A. Hi. I think you bring a project to life by picking something that already fascinates you. If you pick something that hasn't grabbed your interest by 10th grade (metal rusting ... ho hum), it probably won't now; and if you're not interested, it's hard to interest others. Try to think of your past or present hobbies, interests, models, etc., and how rust might have surprised, interested, confused, or inconvenienced you. Maybe your interest was bottle caps, model boats, electric trains, old cars, yard art, antiques, old computers, political buttons, musical instruments, magic tricks, or whatever. You probably won't convincingly feign enthusiasm. Think hard about what already interests you and how rust might impact it. Good luck.

Regards,

A. Hi Bobby. The Iron Bridge crossing the River Severn in Shropshire, England has been standing since 1781. But steel and iron can flash rust in 15 minutes -- so it depends on a lot of things.

But if you are asking how long it will take a plain iron or steel nail to rust when immersed in water for a science project, I think you'll see rust in one to two days. Good luck.

Regards,

A. Hi Malyda. While wearing goggles, snip or sand the barb off those hooks before using them in a kid's science project -- you're making me queasy :-) Although the ancients used bronze fish hooks, you are correct that today's "bronze" hooks are made of steel and are merely the color of bronze. I suspect that bronze hooks are not electroplated with bronze, but simply dipped in a bronze colored lacquer, but would appreciate if someone who works at a fishing tackle company would weigh in on this.

The sentiment on a number of fishing forums is that bronze hooks are the cheapest and least durable of any common finish. A Maryland DNR study found that no fish hooks dissolve away in a practical time period, but that bronze lacquer hooks may be the safest for fish, but probably not by a statistically provable margin (articles.baltimoresun.com/1991-03-20/sports/1991079022_1_barbless-hooks-hook-styles-smaller-fish)

This bronze lacquer is apparently not very impermeable, and does permit the underlying steel hook to pretty rapidly rust, so that's why they are rusting.

Coke, Gatorade, and Apple Juice are all mild acids (www.21stcenturydental.com/smith/education/pH_drinks.html). Rust is more soluble in acids than steel is, with the result that things may not look rusty even if they are corroding faster than they are corroding in water because the rust is dissolved and not visible. When the Coke, Gatorade, and Apple Juice eventually evaporate away, you should see significant rust in the residue.

Regards,

A. Hi Bianca. Unlike your nephew and his fellow students, you haven't been attending science class and covering the subject in school (and receiving those little hints from the teacher), so I would expect you to be having a lot more difficulty with it than them :-)

First things first, are you sure he 100% understands the question? 100%. It's fine to ask a question if don't know the answer, but it only adds still more confusion for him to ask for an answer to a question that he doesn't understand.

Assuming he's past that hurdle, it looks like he's been offered the option to demonstrate any of four factors that affect the reaction rate. I can easily think of two more factors: temperature and agitation. So after he picks one, he has to make sure he can hold the other factors constant, because if they vary they may screw up the cause-and-effect results.

Do any of the 4 factors interest him? Interest is key to a good project! Most kids are more interested in "3." & "4." than the others. But "3." can be very hard to do in some of today's chemophobic classrooms, where real chemicals are often forbidden and the children are expected to learn chemistry from playing with secret recipes like Gatorade & Dr. Pepper (how do you know the acid is responsible for differences when you don't even know what chemicals are in secret recipes? -- it's ridiculous). So "4" is perhaps the project you'd better do for/with him. You can read on this page some of the great approaches to doing "3." or "4.", or combining them, by kids his age and even younger. Also, make sure you have his Science book in hand when you do this, because if you express anything that contradicts the language of his textbook there will probably be demerits. Good luck!

Regards,

A. Hi Sophia. Try to find plain "cut" masonry nails if you can. These are hardened steel with no corrosion proofing. But if you don't readily find them, then just "bright finish" nails.

What you need to avoid is "roofing nails" or "hot dip galvanized" nails as these are as corrosion proof as practical; and you also don't want stainless steel, or aluminum, or painted "paneling" nails.

But be careful in describing your project! Although you want a metal that corrodes fast in order to speed the project along, your subject is NOT what metal corrodes the fastest; your project is which of those three materials corrodes steel nails fastest. Good luck.

Regards,

A. Hi Ella. There is a lot of info on this page already. Simply putting a steel or iron nail, or steel wool [on eBay or Amazon] into water, salt water, or bleach will make it start to rust within a couple of days.

Regards,

The cut nails are by far the best ones to use, but while there is no intentional preservative on them, most are heavily oxidized. Make them shiny with steel wool.

Bright nails normally have a thin coat of zinc electroplated on them, Here again, make them bright steel by a lot of rubbing with steel wool. If you want to make sure that you have removed all of it, put a sample nail in vinegar [in bulk on eBay or Amazon] will corrode metals but will dissolve rust faster than metal, confusing the issue.

The precious metals (gold, platinum, etc.) will not ever corrode. Copper, brass, zinc, nickel, tin and aluminum will corrode, but not rust.

But I don't think you'll want an experiment with multiple variables like all kinds of metals, all kinds of corrosion conditions, and all kinds of preservation techniques. I think it will be better to pick one metal (maybe steel nails), and one exposure condition (salt water OR fresh water, spritzing OR full immersion) if you intend to try multiple corrosion-proofing methods.

Corrosion-proofing methods could include a variety of store-bought paints, vs. dipping in grease, dipping in melted chocolate, waxing, etc.

Regards,

A. Hi Isaiyah. Please have a parent read and interpret this page for you because it has been explained many times on this page that zinc and aluminum cannot rust (although they can corrode). Yes, you need each one in salt water or tap water -- so start a lab book, writing down everything you do and observe. Good luck.

Regards,

A. Hi Osa. If by "higher grade" you mean a more expensive alloy steel with significants amounts of nickel, chrome, or other alloying materials in it, the higher grade steel will corrode slower. A basic reason is that these other metals are not as corrosion-prone as iron, and they form tighter and more adherent corrosion products. 18% chrome essentially makes type 400 stainless steel; 18% chrome and 8% nickel makes type 304 stainless steel.

Even a small amount of alloying metal, like 2% copper or 3.5% nickel can significantly reduce corrosion.

Regards,

Hi Scott. Putting metal into tension does affect the structure and cause galvanic hot spots. The bending also might have increased the surface area. Unfortunately I don't know a quick and easy way to tell which was the more dominant factor. It might be possible to anneal the zinc to remove the stresses and see what happens then.

Regards,

A. Hi Nathan. Steel will quickly rust unless it receives proper pretreatment and finish, but copper and bronze will not remain attractive unless properly finished either. Copper and bronze are so much more expensive than steel that their architectural uses are quite limited.

Regards,

A. Hello John. we appended your inquiry to a long thread which covers it rather completely and offers some other sources. For the purposes of such a test, I don't think it much matters what type of steel, copper, and bronze you get; go for the cheapest, but carefully retain full detail on what you get. What you'll be looking to get from this experiment is not so much the specific result as learning how to properly undertake such projects -- which will include documenting information as accurately as possible. Good luck.

Regards,