Processing and properties of ultrahigh-carbon (1.6%C) steel

An ultrahigh-carbon steel containing 1.6 wt.% carbon (UHCS-1.6C) was processed to obtain ultrafine spheroidized ferrite, pearlite and tempered martensite, respectively. The tensile properties of these structures were evaluated at room temperature. The ultimate tensile strengths of UHCS-1.6C ranged from 930 to 1570 MPa, elongations to failure from 4.4 to 19%, and yield ratios from 0.65 to 0.92. The fracture mechanisms of these structures were clarified based on an examination to the fracture surfaces. The present results indicate that ultrahigh-carbon steels can be easily processed to achieve unique microstructures and properties.