A martensitic microalloyed steel, 25Si2MnCrMo, was developed to meet the demands of the high-strength bars. Microstructure and mechanical properties of the steel were evaluated by using optical metallography, scanning...A martensitic microalloyed steel, 25Si2MnCrMo, was developed to meet the demands of the high-strength bars. Microstructure and mechanical properties of the steel were evaluated by using optical metallography, scanning electron microscopy, transmission electron microscopy, dilatometry and tensometry. Those measurements suggested that the steel consisted of martensite and retained austenite, which existed between the martensitic laths in a stable thin film, and that the steel showed very high tensile strength of 1400 MPa and good ductility of 15% in elongation after 300°C tempering.展开更多
文摘A martensitic microalloyed steel, 25Si2MnCrMo, was developed to meet the demands of the high-strength bars. Microstructure and mechanical properties of the steel were evaluated by using optical metallography, scanning electron microscopy, transmission electron microscopy, dilatometry and tensometry. Those measurements suggested that the steel consisted of martensite and retained austenite, which existed between the martensitic laths in a stable thin film, and that the steel showed very high tensile strength of 1400 MPa and good ductility of 15% in elongation after 300°C tempering.