Tool Steel Bar/Tool Steel Round Bar. Tool steels areCustom to form, cut, shear and mold metals and other materials. Cold work tool steels (D2, D7, A2, O1, S7, S5) areCustom for roll forming, general tool and die applications, progressive dies, and mining. Hot work tool steels (H13, 2714) are sold into the aluminum extrusion die market, die cast