Superquench question?

[Jack Evers]

The recent and active thread on "first anvil build" gives a link to some test data on hardening both mild and tool steel:

http://paaba.net/Pro...ZWeekendMet.htm

These data state that superquench had no effect on mild steel (1018, I suppose since it was stated as about 0.2% carbon) and was no better than brine on tool steel (4140).I do not have a hardness tester, but when a high mileage horseshoeing client of mine was asking for hardened shoes (she was wearing regular shoes out in about three weeks) I did harden some 1018 with it and have it tested. Don't remember the exact numbers but seem to recall mid 40's rather than the reported 18 in this paper. I also had a second test on a worn out shoe to see if the hardening had penetrated - it had.

In several years of hardening shoes and getting good wearability, I also noticed that the nail heads on hardened shoes would wear below the metal of the shoe, something that rarely happens without at least quenching the shoe. i.e. the nail heads wore faster than the shoe even though somewhat protected by the shoe.

Anyone care to comment on either hardness measurement or experience with superquench and low carbon steel.

[atexascowboy]

On horses that were hard on shoes, springing, excess wear, etc., I would quench the ground surface and get great wear on a 1018 shoe as well as a standard keg shoe. Then someone would argue the keg / 1018 shoe is unhardenable. Yeah, it is.

[Larry H]

Jack.....I'll tell you what, although I've never tried it on shoes, I can tell you this....it definitely  works with punches and chisels,.........." If "  someone shows you how it works. I would imagine the angle of the Quench would impact the result. Don't forget to "scrub" it in the liquid

[Jack Evers]

All sounds like my experience. Wonder if they had a batch with faulty or missing ingredients.

When I was in Grad School many years ago, we were next to the nuclear engineering group and they were working on the idea of how to break up the vapor layer to get continued rapid cooling. The superquench did come out of Los Alamos Labs and was based on that idea. It works for me.

[Thomas Dean]

You could contact Robb Gunter and ask him personally. He was one of the develpers of Super-Quench and can give you concrete facts on the subject.

This is his web site;  http://www.g3blacksmithing.com/about.html

[Rich Hale]

I have had positive results with super quench on  mild. For a punch to be used only a few times i would choose superquench and  mild, for long term use, S-7.

I have to wonder about the SQ used  on the above testing for one reason. I used the original formula,,,and have noticed that lately when that recipe is posted it does not mention shaklee basic I,,they just say a water wetting agent. I will not llikely step yup here and do the kind of testing needed but I do wonder,,and I will stick with the original.

[Jack Evers]

On 1/8/2013 at 10:54 AM, Rich Hale said:

 

 

I believe Shaklee basic is no longer made, now it's basic green or something like that. Wasn't the original Basic I with the "I" for their industrial version?

[ThomasPowers]

Remember too that there can be an appreciable difference in carbon content between "mild steel" and A36 that is often sold as "mild steel" these days

[Larry H]

jet dry ( which is sold in the North East, for dishwashers to prevent spots ) is used instead of Shaklee products,( because we never heard of "Shaklee" up here. ) 

[Frank Turley]

When Rob Gunter was at Sandia Labs in Albuquerque, he was getting "super" results by quenching mild steel in caustic soda (lye) / water solutions. Apparently there was an IG inspection and he was told to get rid of the lye, because of the danger of storaage, etc. After ridding his lab of the material, he proceeded to conjure up the super quench formula. Rob would be able to respond to these questions, as he was the source, so to speak.

 

I worked once upon a time with Tex Shively in Oregon and he was a farrier who quenched nearly all of the toes of his mild steel shoes at a bright red heat in water. He didn't perform any tests, but he swore that he got more wear out of the shoes when compared to non quenched.

[WayneCoeArtistBlacksmith]

I make knives from horse shoes and RR spikes.  I quinch in Super Quinch.  My wife carries a Case Equine Special.  I have to sharpen her knife more often than I sharpen my carry knife.  And she will go a lot longer than I before she decides that it needs to be sharpened.

I contacted St. Croix horseshoe company and they told me that their shoes were made from A-36.  There is a lot of difference in 1018 which has 18 points of carbon and A-36 which has a maximum of 29 points of carbon.

[Jack Evers]

Quote from Frank Turley

I worked once upon a time with Tex Shively in Oregon and he was a farrier who quenched nearly all of the toes of his mild steel shoes at a bright red heat in water. He didn't perform any tests, but he swore that he got more wear out of the shoes when compared to non quenched.

Frank, your friend was probably right. A simple qualitative test is just the moment required to bend a bar. This is linearly related to the tensile strength and the tensile strength is related to the hardness. so stick a bar in a vice with a constant amount sticking out and the pull required to bend it is a measure of both the tensile strength and the hardness. I found some old data where I took a length of 1" by 1/4", cold rolled (probably 1018) clamped it in my vice, hooked a spring scale 24 " from the vice and measured the pull to bend it. As received it took 32 pounds, heated and quenched in water, it took 52 pounds or about a 60% increase in both ultimate tensile and in hardness. Heated and allowed to cool slowly as the gas forge cooled it then took 24 pounds. If as Wayne says, those were keg shoes of A36, the result would likely have shown even more difference.

[ibs740]

If you look at the results http://paaba.net/Pro...ZWeekendMet.htm something doesn't make sense. All samples except the Super quench have harder exteriors than interiors. Are the Super quench numbers a typo? Also if Super quench is essentially salt and water why are the SQ #'s half of the salt and water?

TheAnyone care to comment on either hardness measurement or experience with superquench and low carbon steel.

[thingmaker3]

The "total of 72 hardness readings" does not add up either. 2 steels x 3 quenchants x 2 samples per quenchant x 3 hardness test areas = 36. What did they test for the other 36?

[Larry H]

I have to chime in again on this. Ian Lowe......( from Ians world tour ) came to my shop, I mixed up a batch of Super Quench. Ian heated a 3/4 bar of mild steel, made a chisel,  quenched it, and cut off a piece from the same stock. Not a mark on the chisel. If that isn't some kind of proof, nothing is. However......there was no hardness test, just a work test.

[danielpiotte]

I was told that the designation of "A-36" steel is based solely on the steels performance and engineering characteristics( ie. tensile strength,load bearing limit,etc.) The steel industry came up with this so they would not have to meet specific alloy percentages in stuctural steels. I know as a toolmaker if I want 1018 now I have to pay more for it because it must meet the alloy criteria. There are very large disscrepencies between batches and manufacturers of "A-36" steel.

Just my two cents.

 

Daniel

[JHCC]

Reviving an older thread, I just welded up an anvil block from a big chunk of (what I assume is) mild steel. I'm going to do some tests with some of the offcuts, but before I go mixing up a batch of SQ, would it be appropriate for something 2" square? Most of the discussions of it that I've seen seem to revolve around knives and horseshoes, not something with such a larger cross-section.

[ThomasPowers]

I'd worry about the leidenfrost effect.

[JHCC]

Well, isn't that the whole point of the wetting agents in SQ?

[ThomasPowers]

It helps but....

 

[SLAG]

Gentlemen,

A stray thought or two.

Would adding vigorous turbulence  to the quenchant fluid help to overcome the Leidenfrost effect.?

In that effect,  the boiling vapor forms an insulating skin that interferes with rapid cooling of the item.

(moving the object up and down and in a figure eight pattern is used to accelerate quenching.)

A good example of the Leidenfrost phenomenon,  that most of us have seen,  is seen when a drop of water is dropped onto a very hot skillet. Said drop  does not explode into stem. 

Instead the water skitters across the surface for a surprisingly time,  before it boils off.

 Some people have used  high pressure hoses with quenching solution/fluid,  to quench the suspended item.

I know that some anvil foundry's use/have used this method.

I can envision that the system would work just fine for smaller items.

I am not so sure that it would be feasible for quenching a larger "block" of metal in a small smithy, or foundry.

(Herr Hans Richter, can you help me on this subject?)

The foregoing  constitutes some SLAG thinking on the subject.

Regards,

SLAG.

[JHCC]

Leidenfrost effect aside, my main concern is that if SQ does harden an otherwise unhardenable block, would I be running the risk of the outside shrinking too fast and making the block crack?

[Frosty]

I have a hand drill paint mixer I use to make a whirl pool in my quench tank. You still have to rotate heavy stock or vapor pockets will form on the lee side. Should work fine in a water quench too. 

Soderfors quenched their anvils under a water tower that directed a metered amount stream of water on the face. Residual heat in the body did the tempering. 

I was going to copy the water tower technique when I had a notion to cast an anvil with a steel face. I planned on quenching next to "Lake Jake" in the gravel pit down the hill from our place. Bring it to heat in a charcoal forge and quench with a rented 2" trash pump, outlet hose draped over a ladder. 

AND once again we're typing at the same time John. That's an interesting question but I strongly doubt its a concern unless you're quenching high carbon or high alloy steel. To crack as you envision the chilled shell would suffer a tensile failure. This is steel's strongest mode, any stresses built up in the chill would (maybe?) increase work hardening.  That's a wild guess don't quote me on it or I'll think something unnice. 

Frosty The Lucky.

[ThomasPowers]

Charles McRaven mentions using the high pressure hose from the local VFD to harden the face of a substantially repaired anvil in "Country Blacksmithing".  (I suspect brown pop was involved...)

[Frosty]

It'd be my luck to get the anvil to critical temp and the FD get a call and leave me there with an anvil growing BIG crystals (grain). The lake is always there and a 2" pump rents for $40/day, enough charcoal briquettes would cost more.

Frosty The Lucky.