Heat Treating 440C

[Mike Mossington]

Any advice on temperature and soak time for 440C?

I have read several data sheets, where recommendations vary from 2000F (no soak time given) to only 1850F for 5 minutes. I have an Admiral Steel Technical Info sheet that recommends "1850-1950F, hold for 5 minutes, do not overheat(too much time or too high temperature)". Last night I went to Admiral's site, and now the Technical Info sheet reads "1850-1950F, hold for 30-45 minutes, do not overheat(too much time or too high temperature)". Admiral's in-house recommendation has gone from 5 minutes to 30-45 minutes!!

Not sure what guidelines to follow. My practice has been to use 1880F and 15 minutes - with varied results.

Would appreciate suggestions/comments.

Mike

 

[silver_pilate]

1850-1950 is correct. The 30-45 minute soak is typically "per inch of thickness." When working with thin cross sections like we do, the long soaks aren't as important. That said, it is a high alloy steel and need some time at temperature. If you have good temperature control, I'd recommend at least 15 minutes of soak. I typically hold longer as you're not hurting anything.

-Nathan

 

[Jarrett Fleming]

My ht for 440c is 1900 for 45 minutes and two temper cycles at 400 for 2 hours. I hope this answers your question.