"sweating" steel

I was talking to a smith the other day. He said when he uses a
high-grade steel ( higher than SK3 or SK(D?)11 ), the specific nature,
source and name of which he refuses to divulge, the finished, highly
polished product of a bar that has been beaten very many times leaks a
liquid that he has to wipe off every week or so. The "liquid" looked
to me oil or graphite. He said he doesn't know what it is or why it
keeps coming out of the steel. This seemed to ring a bell with me, but
I couldn't find any-thing on the Internet. Does any-one have any
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Sintered powder metal. Once you hit it with hammer oil is being pressed out from pores (assuming that oil or some other lubricant was used during pressing/forming).
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The oil would have to be added after the sintering was done. During the sintering process all oils/lubes are baked out at the begining of the sintering. Oil can then be put back into any remaining pores with a vacuum impregnating process after sintering. This process is very common when making bronze bushings. I find it highly unlikly he would be using this process to make knife blades but only he knows for sure.
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Thanks for the feedback. He is making replicas of Korean swords. He quenches the blade during his forging. Maybe it is this oil that is coming back out. What do you think? Oneota
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Without knowing the steel (chemical and physical descriptions), it is hard to guess how the oil could get IN the steel, so it could come OUT.
Some problems are good ones to just walk away from. This seems like a good candidate.
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