Spring steel and 5160

[lyuv]

It seems common to consider vehicle's spring steel to be 5160. But when I checked with some manufacturers site's, they state a selection of other steels. Even if one of these is just a different coding system for 5160, they cant all be.

My question is - would it be "safe" to assume a "mystery" vehicle spring is close enough to 5160, regarding it'a characteristics and heat treating?

 

[pnut]

I would do a series of break tests with progressively faster quenchants if you're not sure. 

Pnut

[Jasent]

I’ve just made a habit of testing all unknown steel.  I have found coil springs that didn’t harden well in oil but water was good

[ThomasPowers]

Junkyard Rules: 

Rule 1: ALWAYS test if you want to make an item that needs heat treating! 

Rule 2:  In rust we trust!

Rule 3: Never assume that something will still be there the next time you visit.

Rule 4: Never assume that two identical pieces will be made from the same alloy---see Rule 1!

Rule 5: You are responsible for your own Safety.  Those folks driving the heavy equipment might be focused on balancing a load of scrap taking it to the crusher and NOT watching out for you messing in the pile.

Rule 6: Make friends with the yard hands; only takes 1 time to hear "We threw an anvil over there cause we thought you might be interested in it!" to know how much that can pay off. (I've even had "We're going to lunch and going to lock the truck gate; leave all your stuff piled up by the scales if you have to go before we get back.")

Others?

In 39 years of smithing I have run across 1 leaf spring that would not quench harden. It probably was a strain hardened mild steel.

[BartW]

I've run across a couple of springs that don't harden at all, not even in water. It's also probably a location thing.. in the USA most leaf springs are some form of 5160; but in Europe for instance there's a whole slew of steels used to make springs. I've found C70; C80, C90,  9260, 5160 in springs, but also stranger stuff that simply doesn't harden at all.

[ThomasPowers]

A lot of folks seem to think that there must be only one alloy used for an item by manufacturers; while the truth is that if they don't explicitly list the alloy in the specs of what they are selling; they can change what alloy they use 3 times a day if they get a better deal on something and think it will meet the requirements!

[Steve Sells]

there is no law stating what we have to use to make an item, why do people think there is one that forces it on others?

[Jasent]

I think this chart has a lot to do with it.  Many folks think it’s gospel though it is some times correct that’s often not the case and while some of the alloys used will be similar some will not.  Always test unknown steel and don’t assume it’s what you think it is

[ThomasPowers]

I've remarked a number of times that that list can be pretty bogus---like Jackhammer bits as S-7.  We had a member hear that had a decades long career resharpening and heat treating jackhammer bits and he said that he had only seen a handful that were not around 1050 steel. (So when I was asked to resharpen one I treated it as 1050 and had no issues!)

Now if you look in things like Machinerys Handbook under the alloys section it says that S7 would be suitable for  jackhammer bits---and it would; but the cost would be several times that of making them from 1050, which makes decent ones.  Titanium would make GREAT car bodies and frames; you see many of them around on the roads?

Junkyard Rules: TEST EVERYTHING!  I once was getting some stock from an old plow at the junkyard, two nice straps, got home and one was 1080 by spark test and the other identical piece used for the same task was real wrought iron.  (1930's repairs often were like that---you used whatever was to hand and cheap or free!)

[bluerooster]

Looking at that list, I see several like items, bearings for example. Ball bearings listed as 52100, and roller bearings as 4815. So, I suspect the reverse could also be true. Same with springs, and various other components of similar ilk.

[ThomasPowers]

Things like bearing races tend to swap alloys as they go from small to large with the large ones often a case hardened lower carbon steel. (At least my friend who worked as a Metallurgist at Timken Bearings told me this.)

[patrick]

And he was right

[bluerooster]

Yes,  I just disassembled a front hub from a 2010 Chevy van.  I was after the bearing races. The outer race, and housing, are monolithic. One chunk of low carbon steel, with bearing surface carburized. But the inner race is a seperate part, and I believe it to be 52100.