“Hardness” is a concept we use every day to compare objects: fresh bread vs. stale bread, a baseball vs. a softball, or a living room sofa vs. a park bench. In physics (and manufacturing) the definition is a bit more specific: hardness is a measure of a material’s ability to resist localized scratching or deformation by indentation at a specific loading location.

Our understanding of hardness and relative hardness between materials is key to manufacturing metal products. The correlation of hardness with other mechanical properties also makes it possible for us to predict, with a high degree of accuracy, the strength and ductility of a material without submitting it to destructive testing.

Ductility describes a metal’s amenability to being drawn or stretched without breaking. It is one of the crowning mechanical properties of a metal. Without a sound understanding of the science of ductility, manufacturers would be unable to guarantee the safety of their machinery. In this blog, we’ll explain why manufacturers rely on ductility to guide them in casting parts that uphold integrity in service while protecting machinery against catastrophic failure.

Past civilizations had very practical reasons for caring about metal properties. They had to ask questions like “Can I break my enemy’s sword before he breaks mine?” or “How thick does my armor need to be to provide any protection at all?” They might not have known it, but these soldiers and gladiators were primarily concerned with material strength.

In the metal manufacturing industry, mechanical properties play a huge role when choosing the right alloy for each job. Throughout casting and machining processes, as well as during the product's useful life, the chosen material will be subject to many external forces. It’s up to the manufacturers to create products that perform as needed every step of the way. By understanding mechanical properties, manufacturing professionals can make the right choices for materials and processes.