Plate quenching o1?

T

Tin.Man

Joined
Sep 5, 2010
Messages
876
Ideally oil quenching it to get past the nose, then between two precision ground alum plates and clamping to room temp them tempering either still between the plates or otherwise.

Thoughts? Comments, concerns? Appreciate any and all input fellas
 
have done in on non profiled 3/32 thick but would not try any thicker or with bevels cut into the blank too close to call
 
Yea I'd recommend (instead of just plate quenching) doing an interrupted oil quench to below the pearlite nose and then lightly clamping between two plates while it cools to Mf temperature. This will also leave you with a nice straight blade in addition to being properly hardened.
 
Last edited:
Tin.Man said:
Ideally oil quenching it to get past the nose, then between two precision ground alum plates and clamping to room temp them tempering either still between the plates or otherwise.

Thoughts? Comments, concerns? Appreciate any and all input fellas
Click to expand...
I do something similar when working with 1/32" and 3/64" O1. oil quench till black, between 2 weighted plates till room temperature. remove from plates, cold water wash, 1/2 hour in freezer, then temper.
 
It depends on the dimensions of O1 object, the contact area of the plates with your object, the dimensions of the plates and also on the cooling rate you need.

Assuming you want to keep it straight while cooling, it should work if your plates are straight and thick enough to not melt.

In terms of properly hardening your piece, that's harder to say. You will need to do some research into it.

Consider the following:

Heat is conducted from your object into the aluminum plates and dissipated into the surrounding environment (I am assuming air) via convection/radiation. Based on my own research into heat transfers with various quench media, I can say that convection/radiation into the surrounding air is quite slow. It is likely your limiting factor as conduction through aluminum should be very fast. In this case, your aluminum plates will transfer the heat from your O1 to the air but since it can take in more heat than it can lose, it will increase in temperature and act as a heat sink. The temperature of this heat sink will be different depending on the dimensions of your plate. You should do some calculations and ensure your plates are thick enough that the equilibrium heat sink temperature is below the MS.



Side note. I am actually planning on working on a plate quench calculator for common metals. I've done a few using various liquids such as boiling water, lead bismuth eutectic and forced air but those were easy. Plate quenching requires more research. No clue when I will get to doing this.
 
Hey Scott I have a question for you...have you ever experienced cracking during putting your blades in the freezer? I had two knives in a row crack while in the freezer, 2 separate times made from SUJ2 (52100) steel. Both seemed fine after forging, normalizing and heat treating, perfectly straight, then in the freezer they cracked throughout the whole blade, even causing it to curve drastically. I have never tried this with O1 but hesitant to do that now.
 
nickandersonart said:
Hey Scott I have a question for you...have you ever experienced cracking during putting your blades in the freezer? I had two knives in a row crack while in the freezer, 2 separate times made from SUJ2 (52100) steel. Both seemed fine after forging, normalizing and heat treating, perfectly straight, then in the freezer they cracked throughout the whole blade, even causing it to curve drastically. I have never tried this with O1 but hesitant to do that now.
Click to expand...

this was after hardening before tempering and after washing the blades in cold tap water. no cracks or other issues
 
Interesting...I followed that same protocol as well, no snap temper in between. Maybe I'll try a test piece out and see how it fares.
 
The original post says he is quenching in oil first and then going between plates. Not using the plates to quench with. Aluminium is just to slow to quench any non air hardening steel in. I tryied it with thin 15N20 that was flat and it got hard but not anything like a water quench.
 
duurza said:
It depends on the dimensions of O1 object, the contact area of the plates with your object, the dimensions of the plates and also on the cooling rate you need.

Assuming you want to keep it straight while cooling, it should work if your plates are straight and thick enough to not melt.

In terms of properly hardening your piece, that's harder to say. You will need to do some research into it.

Consider the following:

Heat is conducted from your object into the aluminum plates and dissipated into the surrounding environment (I am assuming air) via convection/radiation. Based on my own research into heat transfers with various quench media, I can say that convection/radiation into the surrounding air is quite slow. It is likely your limiting factor as conduction through aluminum should be very fast. In this case, your aluminum plates will transfer the heat from your O1 to the air but since it can take in more heat than it can lose, it will increase in temperature and act as a heat sink. The temperature of this heat sink will be different depending on the dimensions of your plate. You should do some calculations and ensure your plates are thick enough that the equilibrium heat sink temperature is below the MS.



Side note. I am actually planning on working on a plate quench calculator for common metals. I've done a few using various liquids such as boiling water, lead bismuth eutectic and forced air but those were easy. Plate quenching requires more research. No clue when I will get to doing this.
Click to expand...

If you drill holes in the aluminum plate you will have much faster transfer of heat from plate in air , much faster ....depends how many hole you drill / you increase surface of plate and automatically you have higher radiation /
 
Exactly JT. Talking about oil quenching first then using the plates to hopefully eliminate the warp.
 
Tin.Man said:
Exactly JT. Talking about oil quenching first then using the plates to hopefully eliminate the warp.
Click to expand...

my trials with that have worked well both in cooling and preventing warp, but thickest steel was 1/16", plates were 1/2" thick. I would guess that with 1/32" you could use cold plates only and get good results. check this CCT(https://www.dew-stahl.com/fileadmin...zeugstahl/Kaltarbeitsstahl/GB_Cryodur2510.pdf) which shows you have over 40 seconds to get O1 below 400F and still achieve Rc64. i guess ideally you would want 2 sets of plates, the one not in use in the freezer.
 
You must log in or register to reply here.
Back
Top