Investigation on Microstructure and Mechanical Properties of a Low Alloyed UltraHigh Strength Steel
LI Yong1,WANG Chunxu1,TIAN Zhiling1,LIU Xianmin1,ZHANG Jinghai2
1. Institute for Structural Materials, Central Iron and Steel Research Institute, Beijing 100081,China; 2. Special Steel Branch Special Steel Research & Development Center, Baoshan Iron & Steel Co., Ltd., Shanghai 200940, China
Abstract：With ThermoCalc software the equilibrium phases of a low alloyed ultrahigh strength steel 30Cr3 for engine case were studied. By mechanical test, transmission electron microscopic(TEM), scanning electron microscopic (SEM) and XRD observation the performance of 30Cr3 steel was investigated. The results showed that at room temperature the structure components of 30Cr3 steel after equilibrium phase transformation are αFe and carbides (MC、M23C6、M7C3). 30Cr3 steel has good hardenability after normalization,of which microstructure is mainly martensite.During tempering εcarbide is precipitated in martensite laths.The tension strength and yield strength of 30Cr3 steel first rise up with a max.Tension strength of 1870 MPa at 250 ℃, then decline with tempering temperature; the impact energy and fracture toughness decline with increase of tempering temperature.
厉勇;王春旭;田志凌;刘宪民;张景海. 一种低合金超高强度钢组织与性能的研究[J]. 钢铁, 2008, 43(5): 75-0.
LI Yong;WANG Chunxu;TIAN Zhiling;LIU Xianmin;ZHANG Jinghai. Investigation on Microstructure and Mechanical Properties of a Low Alloyed UltraHigh Strength Steel. Iron and Steel, 2008, 43(5): 75-0.
2008, Vol. 43 
