1018 cold rolled steel flat bars have a smooth dark grey oiled surface with sharp defined edges, and accurate dimensions throughout. 1018 cold roll bars have a higher tensile and yield strength compared to hot rolled bars. 1018 is a low carbon steel with good case hardening qualities. Designed for close tolerances, and commonly used for machining, jigs and templates. ASTM A108-07 is the standard specification for steel bar, carbon and alloy, cold-finished.