I did some work in a foundry that produced continuously cast bronze bars and on my first day got a tour. The stock area had a holding pen stacked with bars of different sizes and I was told it was off-limits because it was all military contract supply. When I asked about the production differences (thinking the quality may have been higher) my guide said it all came off the same machinery to the same spec and the only difference was the military stuff had contract and traceability numbers stamped in the end. “And it’s about twenty times the price”
While the may well have come out of the same melt and and appeared identical the military or aerospace items are more expensive for good reasons. First those traceability numbers. There is a large amount or effort behind them. Paperwork in the old days, now computers. Plus storage that will be certified to a greater or lesser extent. They will also be subject to much more inspection almost certainly an assay of their composition and possibly even individual x-rays. This may be external to the foundry so not visible to the workers.
Robert.