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dewat
07-16-2007, 04:36 PM
I've been using the same can of Kasenit for a couple of years now, at first I had good results but lately even after 3 or 4 applications the surface is still soft.

1. heat to orange hot
2. roll the part in Kasenit till well coated reheat to orange
3. repeat 1 & 2
4. when orange hot again immediately quench in 5gal bucket of cool water

So I'm wondering if the Kasenit has gone bad (if it can) or am I over heating the part and burning off the carbon ? It seems to me I'm using the same process I've had good results with before.

Thanks, dewat

Evan
07-16-2007, 04:49 PM
Kasenit is sodium ferrocyanide salt. It can't go bad. It can however be "used up" in the process as the carbon and nitrogen is released when the sodium ferrocyanide breaks down. Once it breaks down it doesn't reconstitute itself. What you return to the can is partly original chemical and partly reacted scale. Time for some fresh Kasenit.

FYI, case hardening with Kasenit isn't just carburizing, treating with carbon. It is carbonitriding as the chemical contains both carbon and nitrogen that is released when heated.

rotate
07-16-2007, 05:24 PM
Don't mean to hijack the thread, but does anyone know where to get this stuff in Canada? I've asked around few suppliers and they all say they don't carry it.

Evan
07-16-2007, 05:32 PM
Ask for Quickhard instead. Same thing and I was able to get it locally. No, it isn't blue.

dewat
07-16-2007, 09:42 PM
Thanks for the reply Evan, but I don't return any to the can, everything that drips off is in a puddle on the firebricks, the instructions say to heat to a bright red so my only other option is to not let it get so hot.... I guess :D .

rkepler
07-16-2007, 09:49 PM
There's a good chance that you're not getting it hot enough, too. The depth of the case is a function of the temperature and soak time, it has to get hot enough then stay there long enough for some carbon to migrate in. If all else fails you can use it in a pack but be careful, I've seen it eat its way out of stainless wrap.

Evan
07-16-2007, 10:19 PM
Hmm. Sounds odd to me. I have never had it fail to work. Exactly what steel alloy are you trying to case harden?

dewat
07-17-2007, 12:30 AM
Its just cold rolled steel, from the same stock I've been using, this is what puzzles me, the same steel, the same can of Kasenit, the same method of heating ( homemade propane burner for the aluminum foundry), the same quenching method, the only thing thats changed is the weather and regular tap water is warm so just to eliminate a variable I put some ice in the water to bring it down to cool, not cold but cool. I've treated some parts 4 times and the surface is still soft. :confused:

Evan
07-17-2007, 01:04 AM
Was the container of Kasenit well sealed? Sodium Ferrocyanide is a salt and as such is very hygroscopic. If it is able it will draw moisture from the air which will convert the chemical to a hydrate form that will not work as a case hardening agent.

Note: I guess that qualifies as "going bad" so I restate my earlier statement to say "properly stored it can't go bad...".

dewat
07-17-2007, 09:40 AM
I'm pretty sure when I got it it was tightly sealed, but on one occasion I did forget to put the lid on, so it did sit opened overnight or longer, ( if it matters, I live in a very dry part of Arizona ).

Evan
07-17-2007, 09:59 AM
Having lived in Arizona I know how dry that is. I can't see it picking up enough moisture in that amount of time to matter. Perhaps the seal on the lid isn't very good. If it is subject to the wide daily temperature swings that can happen in that part of the world it could still suck enough moisture out of the air over time to deteriorate.

You can try pouring out the Kasenit on a cookie sheet and baking it in the oven at 400 degrees for a couple of hours. Don't be concerned about the name "ferrocyanide". It isn't toxic. Sodium ferrocyanide is available as a food grade additive and is widely used in ordinary table salt as a flow control agent. Baking it may give it enough time to revert back from the hydrate and restore the properties. It's the same technique that is used to restore the flux properties on welding rods that have been exposed to moisture.

I would just buy another can of the stuff though.

dewat
07-17-2007, 12:45 PM
I would just buy another can of the stuff though.


I think that's the best course of action, just thought I'd get some feedback, was wondering if anyone else had a similar problem or was it just me.

Thanks, dewat

lynnl
07-17-2007, 03:39 PM
While this stuff is being discussed, I'd like to know its correct pronunciation. Is it pronounced "Casen-nite" (rhymes with kite)? Or "Casen-it" (rhymes with sh.. -well you know what I mean)?