Multiple quench/tempering cycles?

[sph3ric pyramid]

I understand the basics of the heat treat, but I'm slightly confused by the references to multiple quenching/tempering cycles.

What benefits do they offer?

 

[Sethhoward]

Multiple quench and multiple tempering are two different things.

Multiple quench: Take the steel just past critical and quench. Do it again, and now again. Some swear by it when done properly, others who are serious about their metallurgy say it makes no sense at all. There is a long thread about it still floating around this forum right now. It is used with 5160 and 52100.

Multiple temper: After your quench heat the steel to 350f - 450f ( or so depending on the steel ) for one to two hours. Let it cool to room temp and repeat. Some do it a third time. This makes sure that all Matrinsite gets tempered, even some that may have formed during the previous cycle. Pretty much everyone agrees this is a good idea on any steel.


Seth

 

[mete]

As far as tempering, the more complex the steel the more multiple tempering will help.A second or third tempering will help reduce the amount of retained austenite and stabilize any that remains.....Reading the other ongoing thread will explain why multiple quenching is not necessary.

 

[ragnoor]

I am a maker who does a triple quench and triple temper on certain steels. By doing the triple quench you reduce the size of the grain structure of the blade. Reduced grain structure makes a stronger blade. I HT with a forge, so that might have something to do with it, but I get a stronger blade from the triple quench. Does it make that noticeable difference, to me yes?


Ken Beatty

 

[J. Neilson]

I also do a triple quench/temper. Sometimes with the forge, sometimes with a rose bud tip. I believe it works and so do my customers.