Non-alloy steel, also known as carbon steel, is a type of steel that contains only carbon and small amounts of other elements, such as manganese, phosphorus, and sulfur. It is less expensive and easier to manufacture than alloy steel, but it has lower strength and other properties.

非合金鋼，也稱為碳鋼，是一種僅含有碳和少量其他元素（如錳、磷和硫）的鋼。 它比合金鋼更便宜且更容易製造，但強度和其他性能較低。