Cryo treating of S60V

[Kim Breed]

Once S60V is HT does it have to be cyroed right after temper or can it wait a week. or does it make a difference.
Is there a large difference between noncryoed and cyroed S60V?

 

[mete]

About two points higher with cryo. You must quench ,then cryo, then temper twice. Cryo will not do anything if it is done after tempering. Check www.crucibleservice.com for details.

 

[jhiggins]

Can't you cryo between tempers?

 

[mete]

I just had the same question from another forum !!! Pay attention Jeff. Tempering stabilizes retained austenite from further transformation to martensite. If you want to reduce risk of cracking when going from quench directly to cryo you can "Snap Temper". This is done at 300-350F. Tempering at 400F or higher then cryo will prevent getting full hardness.So it's quench, snap temper if you want, cryo , double temper. Cryo will give about 2 points higher hardness with S30V.