Abstract: An indefinite chill roll alloy composition is disclosed containing carbon ranging from 2.5 to 4.0% by weight of the alloy and the carbon is present as free graphite in an amount ranging from 2-7%, preferably 3-6%, of the total carbon. The composition further includes niobium which ranges from 0.3-6.0 % and is present essentially as discrete niobium carbide particles in the alloy. The present invention further includes a chill roll shell formed from the alloy and produced by a method including the steps of providing a molten indefinite chill roll composition, adjusting the composition by adding niobium in an amount sufficient to produce a molten batch containing 0.3 to 6.0% niobium based on the total weight of said molten batch, providing a stoichiometric amount of excess carbon to form niobium carbide and casting the molten batch to form the chill roll shell.