Magic steel

[orezok]

I needed to build some cages for my fruit trees and I remembered that there were still a couple of 20' pieces of #4 rebar left over from my house build 7 years ago. These have been laying on the ground unprotected in the open for the entire 7 years.

Must be some kind of Magic Steel, it doesn't rust.

 

[stub]

it may have something to do with your location....

 

[adirondackmtnman]

It could be galvanized, but it looks too dark to a galvanized coating. It's possible that it's a painted coating that looks a lot like the original steel. try looking at the cut ends, or cutting a little off the end and exposing it to moisture. If it still doesn't rust, maybe the recycled alloy they used to make it is corrosion resistant, hard to believe it would be some sort of stainless alloy though, as they weed out the more expensive metals when recycling...

 

[cqaigy2]

it may have something to do with your location....

Im thinking.

 

[orezok]

Im thinking.

It is kinda dry out here, but 7 years?

Rebar is mostly made from recycled steel, so maybe this batch contained a bunch of stainless or moly.

 

[J_J]

It is probably epoxy coated rebar. It is supposed to protect against corrosion in concrete.

You can see where the rust is coming through due to rough handling. .

Epoxy Coated Rebar - Corrosion Resistant Rebar | Harris Supply Solutions

http://solutions.3m.com/wps/portal/...9E2FVI20E3000000_nid=FM68L69R6Gbe4QCCD178ZXgl

http://www.youtube.com/watch?v=QWUpMWJtgvc

Just grind the coating off and watch it rust.

 

[hosspuller]

Doesn't look like epoxy coated ( thanks JJ for the link) but more likely sprayed with oil or such. Desert conditions are more likely the reason for so little rust. Bring it East and it'll rust for sure.

 

[Rock knocker]

It is probably epoxy coated rebar. It is supposed to protect against corrosion in concrete

Epoxy coated bar is very green

 

[adirondackmtnman]

Doesn't look like epoxy coated ( thanks JJ for the link) but more likely sprayed with oil or such. Desert conditions are more likely the reason for so little rust. Bring it East and it'll rust for sure.

Likely not oil...after all that's what the concrete guys use to get their forms to release...Wouldn't work well trying to get the concrete to bond to the rebar.

 

[adirondackmtnman]

There are a few companies out there marketing a basalt rebar, but I don't think there's any iron content in those products...

 

[/pine]

off the wall I know...but is it possible that decaying organic matter (methane) under the bars was displacing/reducing the oxygen around the bars?

 

[Gary Fowler]

It is just the mill scale that is covering it. It resist rust pretty well, but it will rust in wet or salty conditions.

 

[adirondackmtnman]

It is just the mill scale that is covering it. It resist rust pretty well, but it will rust in wet or salty conditions.

It does look like the gray scale you get when you heat steel to the red/yellow range for forging, although I've never tested it's rust resistance properties, it makes sense since that's just really accellerated corrosion anyway...

 

[orezok]

It's not coated rebar. I've built over $500 million worth of schools and I'm pretty sure I've seen it a time or 2. The bar was mostly exposed with just a little of blow sand over parts of it. No nearby vegetation. I concur that the mill scale has probably protected it except where the blow sand has sand blasted it off. Lots of wind out here.

Of course, with only 0.77" of rain last year, there is not much to get rust started. Strangely enough, there is a third length from the same build that is completely rusted. It was laying in an area of high clay content which may have held more moisture.

 

[orezok]

As far as the zinc chromate coating used on rebar (yellow/green coating), it is usually placed over rebar that has been galvanized for use in bridges and other public works projects. The zinc chromate is there to protect the galvanizing from the corrosive salts in concrete.

 

[lew61]

it may have something to do with your location....

Hello Mojave! Yes, it may have something to do with your, um, location. Plus, if you ever did get some moisture, I'm sure the wind would move it along just fine. :laughing:

 

[dusty3030]

29 Palms flashback - Ahhhhhhhhhhhh!!!!!!!

Ok, sorry about that, had to get that out of my system. Desert aint kind to a boy from the Mississippi River delta region of Arkansas, I kind of like water and humidity. Heat aint the bother but dry don't suit me.

 

[orezok]

29 Palms flashback - Ahhhhhhhhhhhh!!!!!!!

Ok, sorry about that, had to get that out of my system. Desert aint kind to a boy from the Mississippi River delta region of Arkansas, I kind of like water and humidity. Heat aint the bother but dry don't suit me.

My wife, a retired navy Captain previously stationed at Naval Hospital 29P, noted that about half the staff absolutely hated the desert, the other half absolutely loved it. There wasn't much middle ground.

We loved it so we stayed in the desert after she retired. I lived about 25 years in San Diego and she did a couple of tours in SD and one at Camp Pendleton (Oceanside) before we came to the desert.

 

[Gary Fowler]

My wife, a retired navy Captain previously stationed at Naval Hospital 29P, noted that about half the staff absolutely hated the desert, the other half absolutely loved it. There wasn't much middle ground.

We loved it so we stayed in the desert after she retired. I lived about 25 years in San Diego and she did a couple of tours in SD and one at Camp Pendleton (Oceanside) before we came to the desert.

I can certainly understand that, different strokes for different folks and desert is not the stroke for me or maybe I would have a stroke if I lived in the desert.

 

[J_J]

7 years out in the open.

How long do you think the basic gray manufacturer coating would last?

They are already starting to rust out of the steel mill.