DOMO?

[Rob F]

I learned quickly that mild steel can't be hardened, unless you don't want it to, eg; after forging an ornamental element in ''A36'' you make the mistake of quenching it in water.....Then it breaks when you bend it cold.........Back in the 70's when I started a36 was 36, now it's a crap shoot as to what's in it, so beware....and let it air cool....
The term ''steel''was too broad, myself like many others jack around without knowing exactly what you're dealing with......

If I remember correctly A36 is a STRENGTH specification that has NO specific alloy recipe, they can use anything as long as it meets minimum strength-similar to rebar. Whereas cold roll 1018 is also mild steel but with a specific recipe so is much more predictable.

[Grant]

A-36 does have allowable chemistry:

	Carbon	Sulfur	phosphorus	Silicone
A-36	.26 max	.05 max	.04 max	.40 max

 

[JNewman]

If I remember correctly A36 is a STRENGTH specification that has NO specific alloy recipe, they can use anything as long as it meets minimum strength-similar to rebar. Whereas cold roll 1018 is also mild steel but with a specific recipe so is much more predictable.

I have heard that but I don't believe it. Yes the chemistry may be looser than some other alloys but there are standards. This quote is from the ASTM website
"This specification covers carbon structural steel shapes, plates, and bars of structural quality for use in riveted, bolted, or welded construction of bridges and buildings, and for general structural purposes. Heat analysis shall be used to determine the required chemical composition for carbon, manganese, phosphorus, sulfur, silicon, and copper. Tensile strength, yield strength, and elongation shall be evaluated using tension test and must conform to the required tensile properties."
I don't feel like spending the $30 to get the standards from them but they say the heat analysis must be done to meet the specs.

I have chemistry analysis on the material Certs. here in my filing cabinet for a36 steel that I recently bought for a job, if there were no chemical specs. I would assume there would be only physical test certifications.

[JNewman]

A-36 does have allowable chemistry:

You beat me to it Grant

[Grant]

You beat me to it Grant

[Rob F]

A-36 does have allowable chemistry:

I apparently used to strong a word when saying NO recipe. What I was trying to say and I think the allowable chemistry chart shows, is that A36 does not have a specific alloy recipe. The chart shows maximum figures, to me that means anything from none to the amount allowed, just no extra. Compare that to something like 4140 that has a tight range for the important alloys, minimum and maximum quantities. Even 1018 has a min and max for carbon and manganese.
The 36 in A36 stands for 36,000 psi yield strength, which as I understand is the primary goal of the metal.
Please correct as needed, I am always trying to learn

[Bruce Macmillan]

My knowledge of A36 is simply that when I started using it I think the mins and the maxes of new ore and added scrap were adhered to and the product was allot more predictable. No phantom air hardening or having to worry about cooling it in water. The worst thing that ever happened to me when I tried to bend a piece cold and it broke was I almost wound up in the jaws of my 250# air hammer with only broken ribs to show for my evasion tactics.
The mention of fish oil and peanut oil has lit my entrepreneurial flame!....I could make the big bucks selling the new aromatic oils at conferences with names like: ''Peaches N' Diesel''....''Peanut Haze''or ''Cod Ad Nauseum''......Na

[Greg Obach]

the old Surströmming quench, I've heard of that... guess you can't wash your hands off in the quench tank at the end of the day.... water does have its advantages

I did see a sheffield youtube vid where they said that Whale oil is the best... maybe abit hard to get ahold of nowadays ... when i lived out in nova scotia, they did have one of those beast wash up on the shore... it did start to turn abit out in the sun ...ugh

Greg

Many years ago I worked in an old (Norwegian) blacksmith shop and we had a tank of fish oil. Read some technical stuff later that rated it very highly for a quench oil, gave very consistent (and fast) results over a wide temperature range. Only a Norwegian could appreciate the aroma!

[Mike B]

I'd think 0.4% silicone would screw things up pretty good.