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Can brass rust?
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Q. I am doing a science project to see if certain metals rust. I chose copper, lead, steel, aluminum, zinc, iron, and brass. I pretty sure that 4 of those don't rust (copper, lead, aluminum, and zinc) and 2 do (iron and steel) but I'm not sure if brass does.
I don't want to seem stupid when I say it doesn't if it just takes a long time to rust, so if u could please tell me for sure which metals that I chose to do or do not rust. I put all of these metals in a glass jar with water and am waiting to see!
Chloe [last name deleted for privacy by Editor]- Bryan, Texas, U.S.A.
++++A. Brass does rust.
Caren S [last name deleted for privacy by Editor]
- Forest City, Iowa
+++A. Actually brass doesn't rust, Caren :-)
Iron is an element (Fe). And "rust" is defined as the iron oxide corrosion products of the corrosion of iron. So if something does not contain iron (Fe), it cannot produce iron oxide, so it cannot "rust". Steel is iron-based and it rusts; the rest don't.
That does not mean the other metals can't tarnish or corrode, though. In fact, all metals except precious metals like gold and platinum corrode to some degree. It's just that it's not called "rust".
If you scratch the lead you will see that it stays bright only for a little while and then tarnishes. The same thing happens to copper, aluminum, zinc, and brass.
Please note that this answer applies only to science projects because most "brass" that a consumer, hobbyist, or homeowner might see is not really solid brass; rather, it's often a thin plating of brass on steel. And in that case, the steel underneath the brass plating can certainly rust.
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
