52100 anneal question

[comet_sharp]

Hey guys.
I normally use Mr Cashens infor when heat treating my 52100. I use an Evenheat and McmasterCarr 11 second oil. I generally
Normalize 1650
Cycle 1500, 1475, 1450 or 1500, 1350
Aust around 1475 to 1480 and into the 11 second oil. Temper around 365 and get one hell of a kitchen knife.
Now for my question.
Recently I started forging to shape including bevels and distal taper from .187" stock down to maybe .07" at the tip. I do my normalizing and cycles like usual but instead of hardening after thermals I held at 1250°F for 2 hours and turned off kiln. Next day manually straightened and quenched from 1480. Blade is straight as an arrow and hard as can be. I'm wondering if my anneal cycle after the thermals did anything to change the grain structure from my usual routine. I will be grinding and sharpening the blade to test tomorrow but just wondering if anyone has any onsoght. Did my 2 hour 1250° anneal cycle erase the grain I had previously set up or did it just give me a fine spheroidized structure to quench from?
Thanks for any insight.
-Trey

 

[joedhiggins]

You are good. The subcritical anneal does not cause grain growth. It does stress relieve the blade very effectively and virtually eliminates warping in blades with even bevels and consistent carbon content (in other words it won't solve potential warping in a blade with a 1095 edge and a wrought iron spine).

"Normalize 1650 Cycle 1500, 1475, 1450 or 1500, 1350."

I am not a professional by any stretch, but this number of thermal cycles seems perhaps excessive. I imagine you could save yourself a bit of time and anti-scale by dropping that down to a total of 2-3 cycles after normalization, prior to subcritical anneal. And I would probably space the temps out evenly between 1500 and 1350. So maybe 1500, 1425, 1350?

 

[comet_sharp]

Thank you for the response! And yes I meant I either do a cycke of 1500, 1475, 1425 ( 3 cycles) or save time with just 1500 to 1350 after normalizing but so actually like your suggestion of 1500, 1425, 1350. Thank you again.
-Trey

You are good. The subcritical anneal does not cause grain growth. It does stress relieve the blade very effectively and virtually eliminates warping in blades with even bevels and consistent carbon content (in other words it won't solve potential warping in a blade with a 1095 edge and a wrought iron spine).

"Normalize 1650 Cycle 1500, 1475, 1450 or 1500, 1350."

I am not a professional by any stretch, but this number of thermal cycles seems perhaps excessive. I imagine you could save yourself a bit of time and anti-scale by dropping that down to a total of 2-3 cycles after normalization, prior to subcritical anneal. And I would probably space the temps out evenly between 1500 and 1350. So maybe 1500, 1425, 1350?