运用电子显微镜和化学相分析等多种实验手段研究了Ti微合金化高强耐候钢中的析出物,并在热力学计算的基础上分析了其析出过程.结果表明:钢中主要存在TiC,TiCN,TbC2S2,TiN等析出物,连轧前TiN的析出过程已基本完成;大量纳米尺寸的TiC球形析出物粒子在铁素体的位错线上分布;Ti含量增加改变了MC相的粒度分布,小尺寸粒子的体积分数显著增加,增强了沉淀强化的效果.
Many experimental methods such as electron microscopy and chemical phase analysis were used to study the precipitates of high-strength weather-resisting steel with titanium addition, and the precipitation process was analyzed based on thermodynamics calculations. The results showed that the main particles in the steel were TiC, TiCN, Ti4C2S2 and TiN, and almost TiN particles have precipitated before hot rolling. A large number of nanometer TiC particles distributed on dislocations in ferrite. The size distri- bution of MC phase changed with increasing titanium content. The obvious increase in volume fraction of small scale particles heightened the yield strength of the steel through precipitation strengthening.