Abstract: A carbon or low-alloy steel is provided with improved machinability. The carbon content of the steel is less than 1.5% and the sum of the alloy elements contained therein is less than 9%. The steel contains oxide and sulfide inclusions, and the chemical composition of the steel includes 0.1%≦Mn, 0.01%≦Al≦0.05%, 0.025%≦S≦0.3%, 0.002%≦Ca, O≦0.0015% by weight; the “KO oxides” cleanness index is less than 30, all the oxides are lime aluminates, and the average calcium content of type 2, type 3, type 4 and type 5 inclusions is less than 30%. A process of manufacturing such steel and an oxide-core wire for its manufacture are also provided.

Abstract: A carbon or low-alloy steel is provided with improved machinability. The carbon content of the steel is less than 1.5% and the sum of the alloy elements contained therein is less than 9%. The steel contains oxide and sulfide inclusions, and the chemical composition of the steel includes 0.1%≦Mn, 0.01%≦Al≦0.05%, 0.025%≦S≦0.3%, 0.002%≦Ca, O≦0.0015% by weight; the “KO oxides” cleanness index is less than 30, all the oxides are lime aluminates, and the average calcium content of type 2, type 3, type 4 and type 5 inclusions is less than 30%. A process of manufacturing such steel and an oxide-coated wire for its manufacture are also provided.

Abstract: A carbon or low-alloy steel is provided with improved machinability. The carbon content of the steel is less than 1.5% and the sum of the alloy elements contained therein is less than 9%. The steel contains oxide and sulfide inclusions, and the chemical composition of the steel includes 0.1%≦Mn, 0.01%≦Al≦0.05%, 0.025%≦S≦0.3%,0.002%≦Ca, O≦0.0015% by weight; the “KO oxides” cleanness index is less than 30, all the oxides are lime aluminates, and the average calcium content of type 2, type 3, type 4 and type 5 inclusions is less than 30%. A process of manufacturing such steel and an oxide-core wire for its manufacture are also provided.