关键词: S600MC高强钢, 三段冷却工艺, 平整, 力学性能

Abstract: The effects of hot-rolled three-stage cooling and temper-rolling processes on mechanical properties of 2.3 mm 700 MPa grade Nb-Ti micro-alloying S600MC high strength steel strip (/% : 0.07C, 0.15Si, 1.50Mn, 0.015P, 0.003S, 0.025Alt, 0.015Nb, 0.08Ti) are studied. When end rolling at 870 as intermediate temperature decreasing from 670 X. to 580 °C , the yield strength increases from 577 MPa to 600 MPa, the tensile strength basically remaines unchanged (774 MPa to 784 MPa) , the elongation decreases from 24% to 21% , and the yield ratio increases by 0.04. When the coiling temperature increases from 150 °C to 250 °C , the mechanical properties remain unchanged. The yield strength of high strength steel with primary temper-rolling process increases by 20 MPa to 43 MPa, while the tensile strength changes slightly and the elongation decreases by 2-5 percentage point. The yield strength increases by the secondary temper-rolling process significantly to 101 MPa, while the elongation decreases by 8 percentage point, which is adverse to comprehensive properties.

Key words: S600MC High Strength Steel, Three-Stage Cooling Process, Temper-Rolling Process, Mechanical Properties