Torq444...
Hmmmm... another alloy I'm unfamiliar with.
Carefully re-read QQ-N-286. I think what you want to know is embedded within the spec [word-search 'grain']. The ASTM specification for grain size determination, plus several other relevant citations about grain, are present and are fairly explicit.
CAUTION.
The following referenced MIL-STDs are DoD/USN 'Controlled Distribution', which means You have to have a 'need-to-know' to get them. IF serious about using this material then You should have them for a complete understanding of it... and MAY include info on how to control, and inspect-for, this alloy's grain size/quality.
MIL-STD-1684 - Control of Heat Treatment.
MIL-STD-2132 - Nondestructive Examination Requirements for Special Applications.
Regards, Wil Taylor
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