Steel plate identification

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warmstrong1955
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Re: Steel plate identification

Post by warmstrong1955 »

That's where we used the most Pete......buckets & truck boxes. Quite a bit in the mill though, and that's where it got more difficult, as the parts required more drilling & machining, than just preheating and welding like for a mucker bucket.

Here's some anvil plates I made for a hammer mill. I did some in AR400, and some in AR500. That groove down the middle, is 3/4" deep, and 16" long. With the insert face mill I have, and if it was A36, or A572, it would have been a piece of cake. AR500, not hardly. About 1/3 the RPM, and slow depth per cut, as well as feed. Flood coolant, and I'm not set up for flood for real, so another mess. Easy to tell when dullness was upon the inserts....things started to scream. Also, a knee mill.....is not really the toy for stuff like this. Yeah.....it'll do it, but it takes a while.
The drilled holes, and the tapped holes, all done with HSS. At least that wasn't so bad.

I don't do these anymore....and I'm happy about that. :)
100_1400.jpg

Bill
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pete
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Re: Steel plate identification

Post by pete »

Thanks for the pics and machining tips Bill. Tough stuff for sure. I might hang onto what I have until or in case something comes up to best suit it's strong points. LOL, in other words for now I'll side step it's tool eating habits. :mrgreen: A whole lot of our mill parts got sent out to specialty company's for heavy rubber vulcanizing. Expensive for sure, but they seemed to stand up to abrasion better than even the AR plate. The ball mills just used off the shelf rubberized liners in the highest wear areas.
choprboy
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Re: Steel plate identification

Post by choprboy »

Well, I picked up another unmarked piece of 1/2" plate from the scrap yard today. They shot their gun at it for me (learned a new acronym today... I think is was a LIBS Laser-Induced Breakdown Spectroscopy instead of XRF). Unfortunately it didn't give an ANSI grade, said the new plate was "0.5CrMo", about 96.5% Fe, 1.5%Mn, 0.5%Cr, and 0.5%Mo, plus a bunch of other smaller constituents. I was a bit worried about the manganese, but a piece of scrap steel tube nearby came in as unknown with 1.2%Mn and 0.25%Cr and Mo, so I gave it a chance. Wish I had brought a piece of the old plate to test, but I didn't know they'd have the gun out.

The new plate is still a bit harder than A36 channel iron, but a HF 1/4" HSS bit went thru it in one pass without much difficulty.
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warmstrong1955
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Re: Steel plate identification

Post by warmstrong1955 »

pete wrote: Mon Oct 07, 2019 8:09 pm Thanks for the pics and machining tips Bill. Tough stuff for sure. I might hang onto what I have until or in case something comes up to best suit it's strong points. LOL, in other words for now I'll side step it's tool eating habits. :mrgreen: A whole lot of our mill parts got sent out to specialty company's for heavy rubber vulcanizing. Expensive for sure, but they seemed to stand up to abrasion better than even the AR plate. The ball mills just used off the shelf rubberized liners in the highest wear areas.

Yeah....I agree. AR has it's places, for sure, but now, most of what I do, it's not worth the trouble.
If I don't have to, or it's not something 'easy', where I can use some AR....I don't. I have some odds & ends laying around still. Good place for it....laying around..... :)

We started using some rubber, and rubberized parts in the early 80's at a silver mine I worked at, but mostly in the mill. Ball mill liners, were one of the first things. They lasted a lot longer than nihard, and were a whole lot easier to change out. (That's a dirty thankless job) Got some made for the scoop box....and on and on. Simplified......rock will bounce, giving you more rock on rock, instead of sliding & grinding, giving you worn out steel. It's not a lot of bounce....but it works!
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warmstrong1955
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Re: Steel plate identification

Post by warmstrong1955 »

choprboy wrote: Mon Oct 07, 2019 8:33 pm Well, I picked up another unmarked piece of 1/2" plate from the scrap yard today. They shot their gun at it for me (learned a new acronym today... I think is was a LIBS Laser-Induced Breakdown Spectroscopy instead of XRF). Unfortunately it didn't give an ANSI grade, said the new plate was "0.5CrMo", about 96.5% Fe, 1.5%Mn, 0.5%Cr, and 0.5%Mo, plus a bunch of other smaller constituents. I was a bit worried about the manganese, but a piece of scrap steel tube nearby came in as unknown with 1.2%Mn and 0.25%Cr and Mo, so I gave it a chance. Wish I had brought a piece of the old plate to test, but I didn't know they'd have the gun out.

The new plate is still a bit harder than A36 channel iron, but a HF 1/4" HSS bit went thru it in one pass without much difficulty.
We got a gun like that for assaying gold & silver....long time ago. Big old thing, made in France. Wasn't bad really....if you took enough shots at an area, and let it average things.
We called it 'Le Gun', and 'La machine'.

That sounds like you got more AR plate. I'd have to peek at a book or two to sort it out.....not up on the chemistry like my Dad was. He was a metallurgist.
Hope for AR 360, or AR400...... :)
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warmstrong1955
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Re: Steel plate identification

Post by warmstrong1955 »

I cheated....and used the interweb-thing-a-ma-doodle......

AR400: http://www.matweb.com/search/DataSheet. ... 63aa1c7f9c

Varies by mfg....but there ya go.
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choprboy
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Re: Steel plate identification

Post by choprboy »

Yeah.. I was worried about the Mn but I couldn't remember off the top of my head. The square tube reading gave me pause on what I remembered and the carbon reading was very low. Perhaps (hoping) it is not an accurate reading (nothing was cleaned before hand so...). That is disappointing if it was an accurate reading. There was only one other piece of 1/2" about the right size without having them cut up another and I had to make a decision.They were quite surprised that a piece of AR may have slipped out before (they charge about 3-4x as much for it to the home gong builders).

I may do and abusive heat test tomorrow to see if it cracks. Really hot weld a couple coupons together and quench them in water.
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warmstrong1955
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Re: Steel plate identification

Post by warmstrong1955 »

You can weld AR quite successfully, should you be making a weldment of some kind out of the plate.
You just need some preheat....and 1/2" plate doesn't take much.
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Harold_V
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Re: Steel plate identification

Post by Harold_V »

choprboy wrote: Mon Oct 07, 2019 11:24 pm and the carbon reading was very low.
Hmmm. That's possibly a sign that the material in question is a maraging steel, which lends itself quite nicely to welding. That family of alloys is precipitation hardening, so it does not rely on carbon to get hard. It hardens by simply heating at a reasonably low temperature (below 1,000°F) and being held for a prescribed period of time. With low carbon, cracking isn't an issue.

H
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choprboy
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Re: Steel plate identification

Post by choprboy »

Well... a bit inconclusive testing today. The new plate machines with HSS just fine. With the insert facemill and the same speeds/feeds: new plate - tan to light purple chips, 300M (4340) - dark brown to dark purple chips, old plate - flaming orange stringy chips (like lathe hard turning videos). I took a 2"x4" coupon from the old and new plates and welded a few beads on both, nothing apparent different; welded big beads until half the coupon was orange hot and quenched in water, no cracks apparent. But strangely the old plate coupon is now readily drill-able. So the old plate was definitely hardened by some method.

I think the new plate will work for what I need... now just trying to figure out how much handwork I have to do as the pieces are too big to fit on my mill directly. I may see if I can find someone local to CNC precision drill the required holes on a welded up assembly.
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warmstrong1955
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Re: Steel plate identification

Post by warmstrong1955 »

Mystery metal ya have there.....
If you can machine it, and weld it, doesn't really matter much in the grand scheme of things.
(I been there!)

Bill
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