EN 10020:2000

Further refinement of these categories is based on "main quality classes," which reflect the primary properties or intended applications of the metal:

Before the widespread adoption of European standards (Euronorms), individual nations maintained their own classification systems, such as DIN in Germany or BS in the UK. This fragmentation created barriers to trade and technical collaboration. EN 10020 was introduced to harmonize these divergent systems, providing a single, unambiguous method for defining what constitutes "steel" and how different steels relate to one another. en 10020 pdf

What is EN 10020?

Non-alloy Steels: Often referred to as carbon steels. For a steel to be "non-alloy," the content of any single element must not reach a specific limit defined in the standard (e.g., Manganese < 1.65%, Silicon < 0.60%, Copper < 0.40%). EN 10020:2000 Further refinement of these categories is

B. Stainless Steels