Appropriate conversion of hardness 304L

Are you dealing with annealed material?
Or has it been worked to some higher hardness?
And what scales are you trying to convert between?

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P.E. Metallurgy, consulting work welcomed

Either cold worked or annealed. I need to be able to convert between microhardness (Knoop/Vickers) and Rockwell.

For the cold worked material you will need to build your own conversions.
I have never found the tables to be great for that, but you could use the Ni alloy table in a pinch.
I had better luck converting from Superficial Rockwell scales.
For annealed material it is tougher because you usually can't use Superficial Rockwell.
Isn't there a table marked Austenitic Steels? That might be closer for annealed products.

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P.E. Metallurgy, consulting work welcomed

Concur with EdS.
I will not accept conversion (ASTM E140) from microhardness to macrohardness. If I must do it I will use a reference block of similar composition in a similar condition.

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