One-Step Quenching and Partitioning Process for 20CrMnTi Steel

In order to improve the comprehensive mechanical properties of 20CrMnTi steel plate, the one-step quenching and partitioning heat treatment was carried out. The microstructure of 20CrMnTi steel was analyzed by optical microscope, X-ray diffractometer, and scanning electron microscope, and the mechanical properties of 20CrMnTi steel were measured by tensile test. The results indicate that the microstructure of 20CrMnTi steel plate is mainly composed of martensite, ferrite, and residual austenite, and the volume fraction of residual austenite is 4%. The offset yield strength (Rp0.2) and tensile strength (Rm) reach above 550 MPa and 1150 MPa, respectively. At the same time, the maximum total elongation (Agt) and elongation after fracture (A50) exceed 10% and 15%, respectively. The strength plastic product exceeds 17,000 MPa·%, indicating good comprehensive mechanical properties.