K329 / A8mod

[Revolverrodger]

Hello !
I am currently working on a new knife in K329 aka A8mod. It’s a big chopper and I would like to get the best balance between edge stability, toughness, stain resistance and edge holding
I was wondering if anyone has experience with this steel and suggestions for heat treatment ? Any suggestions for a good Austenitizing and Tempering temperature combination ?

Thanks
Alex

 

[Larrin]

1900°F for 30 minutes, quench, temper at 400°F. If you have cryo add it after the quench.

 

[Revolverrodger]

1900°F for 30 minutes, quench, temper at 400°F. If you have cryo add it after the quench.

thanks Larrin !
Am I correct to say that a lower temperature temper (200oC vs 500oC) would be better to retain soluble chromium (more corrosion resistance / lower carbide volume) ?

 

[Larrin]

thanks Larrin !
Am I correct to say that a lower temperature temper (200oC vs 500oC) would be better to retain soluble chromium (more corrosion resistance / lower carbide volume) ?

The low temper range results in higher corrosion resistance. Carbide volume isn't much different between the two because the only carbides that form with high temperature tempering are the very tiny tempering carbide variety. The volume of them is very small. Way less than 1% carbide.

 

[Revolverrodger]

Thanks for the clarification
It’s great when a metallurgist puts some science in the art of knife making

The low temper range results in higher corrosion resistance. Carbide volume isn't much different between the two because the only carbides that form with high temperature tempering are the very tiny tempering carbide variety. The volume of them is very small. Way less than 1% carbide.