The CEV value (carbon equivalent value) is used to determine the carbon equivalent of steel in relation to other alloy components. The hardness of steel is determined by its composition. The carbon content plays a decisive role here, but other elements also have and impact.
This can be quantified in a so-called carbon equivalent. This is a number that is a measure of the hardness of steel. This formula was developed at the time when high-strength steels still had a relatively high carbon content. The CEV value is particularly important for assessing the weldability of the material, as it is highly dependent on the carbon content.