The selection of stainless steel and aluminum alloys often is centered around strength, ductility, elongation, and hardness. These properties indicate how a metal’s building blocks behave in response to an applied load. They are effective metrics for managing the limits of a raw material; that is to say, how much it will bend before it breaks. The raw material must be able to withstand the forming process without breaking.
Destructive tensile and hardness tests can be a reliable, cost-effective way to determine mechanical properties. However, these tests are not always as reliable once the thickness of the raw material begins to constrain the dimensions of the test specimen. Tensile testing a flat metal product certainly still is useful, but benefits can be gained by peering one layer deeper into the grain structure that governs its mechanical behavior.