RD of Microalloyed Ultrafine HSLA Steel in Masteel's CSP Line

摘要

This paper gives the lab simulation CSP ultrafine steel production process, shows its results and the Masteel's CSP ultrafine steel production results by microalloying and TMCP. Using microalloying and TMCP, in the CSP lab simulation process, the designed Nb-bearing steel of 0.05% C, 0.16%Si, 1.33%Mn, 0.008%S, 0.006%P, 0.026%Nb can get the average size of ferrite is 4.26 μm ultrafine microstructure for six passes rolling and cooling by air, its yield strength is 445 MPa, tensile strength 535 MPa and the elongation 34%. For seven passes rolling and cooling by water, The average size of ferrite is 3.70 μm, its yield strength is 510MPa, tensile strength of 590 MPa and the elongation 30%; in Masteel's CSP line, yield strength more than 490MPa, tensile strength more than 580 MPa and the elongation more than 24% strip can be produced. Its grain size is less than 4μm.