Refer to table 2 for "Mechanical propperty limits for Die Forgings" of ASTM B247. The note with superscript 'C' says:
C These values apply to standard specimens. For the heat-treatable alloys the thicknesses shown are the maximum thickness at time of heat treatment for which the indicated...
We have received a block of 2024 for heat treatment to T4 temper. Its size was 200x 200x 300 mm approx. Customer stated that it is "forged". It was Solution treated and then aged. After ageing the block was split into two halves(crack was not visible at the stage of quenching). The failure...
High strength low alloy steels Jobs were quenched and tempered to a hardness of 40-41 HRC. Subsequently they were cleaned by degreasing and pickling, then oxidized for corrosion protection. After the surface treatment they were supposed to be baked as soon as possible as per MIL-DTL-13924D...
To evaluate the response to heat treatment, ASTM A276 recommends to measure hardness on samples with a minimum section of 9.5 mm. As hardness can be measured on lower section thickness reliably as well, then why section thickness is restricted to a minimum of 9.5mm by specification?
