D2 in an oven with product 1

[TomWL]

Is there any danger with putting D2 parts in an oven heated to between 500-1000F with medical stainless steel product? I've been told the D2 could outgas chromium but I haven't found anything to confirm that.

 

[EdStainless]

It had better not outgas at those temps.
Besides the SS parts will have Cr also.
I sure hope that your SS parts are being treated at the lower end of that temperature range, unless you are aging PH grades or tempering martensitic alloys.

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[TomWL]

Thanks EdStainless. I should have said SS and nitinol for that temp range but it doesn't seem like the D2 would pose a problem. With the D2 having already been heated to 1850 for hardening, I would think anything that would happen already did but I just wanted to make sure.

 

[EdStainless]

The only real issue is the cleaning of the D2 prior to tempering.
Since you are likely air cooling this shouldn't be a problem.
We used to temper D2 at 350F as soon as it had cooled enough to handle.
Then we would go back and re-temper to get the properties that we wanted.

https://www.hudsontoolsteel.com/technical-data/steelD2

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[TomWL]

Yeah we use D2 pretty regularly in our punches and dies and typically temper at 400 to get 59/60 Rc. That's why I want to switch to D2 from CPM 10V. The CPM isn't holding the hardness and cutting edge that I think D2 would give us after basically tempering it over and over again in the production oven.

 

[EdStainless]

What temper on the 10V?
Are you sure that the hardness is the issue? 60-61 on 10V is fairly standard.
What microhardness values are you getting?
In my experience 10V has similar toughness to D@ and 4x the wear resistance.
The V in 10V will always give it better wear resistance at the same hardness.
Are these fairly small parts? Have you looked at quenching from 1825F with a double 450F temper?

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[TomWL]

The CPM blades come in from the vendor at 60/61 but after a couple hundred cycles in and out of the production oven between 500-1000, they measure 43-48 on our rockwell tester.

 

[EdStainless]

If you are using the 10V at up to 1000F you need to quench from 2025-2050F and then temper at 1025F.
The hardness should be about 61-62 and it should never drop (OK, it will drop a little over hundreds of hours).
With a 1025F temper D2 should be about 58, and it will slowly drop over time.
You might consider M4 or T15 for this application.

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[TomWL]

Good info. Thanks for your help EdStainless