Re: Heat Treat - Verifying mechanical properties on heat treated material per the AST
Which ASTM spec? For instance, ASTM A105 allows you to use the mechanical properties found from one heat treat lot (providing it is the same mill heat lot) and use those values on subsequent heat treat lots if the same cycle is used and the furnace has a recorder - not a direct quote but the substance is the same.
Are you certifying to that ASTM spec? Has the customer given you a variance from the ASTM spec?
Where is the data / proof there are no product integrity issues in your overall or a specific heat cycle ?
What does your risk assessment address?
There is a correlation between hardness values and tensile properties - if you have enough statistical data, then one might be able to use just hte hardness test as verification of a proper process.
Overall, a process - special or not - requires a feedback function in order to ensure the process was effective.
Depending on the end product's form, fit, or function, I would be very concerned about not having an effectively implemented feed-back process and it would definitely raise product integrity issues.