Heat treat foil

K

Kunklec

Joined
Aug 21, 2006
Messages
230
I did HT on S30V with stainless foil and AL plates. Quenched from 1960F. Never had problem before. This time, the foil welded to the blade. Had to grind it off. Not a big problem, but not sure why it happened. Tried same process with another blade, but this time rubbed soapstone on blade before sealing in foil. Same steel, same foil, same temp. but did not weld. Blade came out very clean. Foil is high temp stuff, supposedly good for over 2000. This was the first time this happened, after treating a number of blades with same process. Any thoughts or similar experiences?
Chip Kunkle
 
Kunklec said:
I did HT on S30V with stainless foil and AL plates. Quenched from 1960F. Never had problem before. This time, the foil welded to the blade. Had to grind it off. Not a big problem, but not sure why it happened. Tried same process with another blade, but this time rubbed soapstone on blade before sealing in foil. Same steel, same foil, same temp. but did not weld. Blade came out very clean. Foil is high temp stuff, supposedly good for over 2000. This was the first time this happened, after treating a number of blades with same process. Any thoughts or similar experiences?
Chip Kunkle
Click to expand...

This also happened to me with RWL-34 knives. I guess when the inside surface of the foil is too clean, chances of a weld is higher. So nowadays I spray tiny bit of WD40 inside of the envelope, it prevents from welding to the blade...
Emre
 
Emre has the answer. Spray the packet and blade with WD-40, let the excess run out, and seal the packet.

Also, considering that the foil is good to 2000F, you were only 3% below that t 1960F. Just the swing of your oven during a heat up cycle could be enough to raise the super thin foil above 2000F momentarily.
Stacy
 
A little pure Talc powder dusted on the steel seems to prevent the welding issue.
 
Thanks for the reponses. Seems like the solution is to put something on the blade to prevent welding. This is the high temp foil, type 309, good up to 2140. Not sure why it did this but will put something on blades from now on just in case.
Chip Kunkle
 
Just a small hint. Don't peek. When the envelope cools, it's almost like shrink tubing. It has to happen once - when you quench - but peeking is just tempting the universe to poke you in the eye.

Rob!
 
wrap the blades in a layer of newspaper. That will prevent contact between the blade and the foil. Simple is best.
 
You must log in or register to reply here.
Back
Top