What is the designation for silicon manganese steel in the SAE classification system?

Silicon manganese steel is designated as 92xx in the SAE classification system. This classification indicates that the alloy contains significant amounts of both silicon and manganese, which are important for enhancing the strength and toughness of the steel. The presence of silicon improves the steel's resistance to oxidation and also helps in deoxidation during the steelmaking process. Manganese, on the other hand, contributes to hardenability and improves the overall strength of the steel.

The "92" in the designation specifically denotes that the steel has a base composition primarily of iron, along with silicon (Si) and manganese (Mn) as key alloying elements. This classification provides a systematic way to identify and categorize various types of steel alloys based on their composition and properties.