Pellini explosion bulge test

Cited as the foundational toughness-testing work from the 1950s and 60s that supports HY80 confidence but does not yet exist for HSLA steels — hence submarine designers' conservatism.

You can see how HSLA steels can save tens of millions of dollars per ship. So the surface people use them, and some of the submarine people are conservative. Why are they conservative? They believe that there's not enough history on the toughness of the HSLA steels. They don't have all the work that was done in the 50s and 60s on the explosion bulge test. I showed you the explosion bulge test that Pellini did. They basically take it under water and they make a weld and they hit it with an explosive charge, and they get all those shock waves from the explosion, and they see if the thing will deform.