Ti含量对IF钢再结晶温度及力学性能的影响

Effect of Ti content on recrystallization temperature and mechanical properties of IF steel

通过硬度试验、拉伸试验、场发射扫描电镜(SEM)和透射电镜(TEM)观察,研究了Ti含量对IF钢再结晶温度的影响,并研究了不同Ti含量IF钢冷轧后在不同退火温度下的性能变化。结果表明,随着Ti含量的降低,IF钢中纳米析出物尺寸减小、分布稀疏且体积分数降低,钉扎作用减弱,再结晶温度下降;低Ti含量IF钢经630℃退火保温10 h后,屈服强度为198 MPa,抗拉强度为312 MPa,伸长率为36.78%,应变硬化指数(n值)为0.25,塑性应变比(r值)为2.42,符合超深冲钢的性能要求。

Effect of Ti content on recrystallization temperature and mechanical property change of the cold-rolled IF steel annealed at different temperatures was studied by means of hardness test, tensile test, field emission scanning electron microscope(SEM) and transmission electron microscope(TEM). The results show that the size, distribution and volume fraction of nano-precipitates in the IF steel decrease with the decrease of Ti content, and the pinning effect and recrystallization temperature decrease. After annealing at 630 ℃ for 10 h, the yield strength, tensile strength, elongation, strain hardening exponent(n value) and plastic strain ratio(r value) of the IF steel with lower Ti content are 198 MPa, 312 MPa, 36.78%, 0.25 and 2.42, respectively, which meet the performance requirements of ultra-deep drawing steels.