k]The formation mechanism of acicular ferrite and its microstructural characteristics in 430 ferrite stainless steel with TiC additions were studied by theory and experiment. Using an “edge-to-edge matching” model, a 5.25 mismatch between TiC (FCC structure) and fer-ritic stainless steel (BCC structure) was identified, which met the mismatch requirement for the heterogeneous nucleation of 430 ferritic stainless steel. TiC was found to be an effective nucleation site for the formation of acicular ferrite in a smelting experiment, as analyzed by metallographic examination, Image-Pro Plus 6.0 analysis software, and SEM-EDS. Furthermore, small inclusions in the size of 2–4 μm increased the probability of acicular ferrite nucleation, and the secondary acicular ferrite would grow sympathetically from the initial acicular ferrite to produce multi-dimensional acicular ferrites. Moreover, the addition of TiC can increase the average microstrain and dislocation density of 430 ferrite stainless steel, as calculated by Williamson-Hall (WH) method, which could play some role in strengthening the dislocation.

通过理论和实验研究了430 TiC添加铁素体不锈钢中针状铁素体的形成机理及其显微组织特性。使用“边对边匹配”模型，确定了TiC（FCC结构）和铁素体不锈钢（BCC结构）之间的5.25不匹配，满足了430铁素体不锈钢异相成核的不匹配要求。通过金相检查，Image-Pro Plus 6.0分析软件和SEM-EDS分析，发现在熔炼实验中，TiC是形成针状铁素体的有效成核部位。此外，尺寸为2-4μm的细小夹杂物会增加针状铁素体成核的可能性，次级针状铁素体将从初始的针状铁素体同情地生长，产生多维的针状铁素体。此外，通过Williamson-Hall（WH）方法计算，添加TiC可以提高430铁素体不锈钢的平均微应变和位错密度，这可能在增强位错方面起一定作用。