Different from previous work, evolution of shape, size distribution, total number density, and distribution characteristic of TiN was systematically investigated in Fe–Al–Ti–O–N alloy with a low concentration of alloying elements during isothermal holding at 1273 K and 1573 K. The holding time varied from 0.5 to 12 hours. TiN was saturated in each alloy, and it was separated from oxides prior to thermal holding. TiN > 0.5 μm was analyzed by automatic SEM-EDS. The results show that the size of TiN follows lognormal distribution in each alloy. Thermal holding is invalid to modify the cuboid shape of TiN; it enhances the concentration of large TiN on the grain boundary of alloy. Oswald ripening of TiN is not apparent in any alloy during thermal holding at either holding temperature. The relation between the average size of TiN and the holding time does not conform to the LSW equation. Size distribution of TiN during thermal holding is comprehensively affected by the supersaturation degree of TiN, the molar ratio of Ti/N in alloy, the original distribution of TiN in as-cast alloy, and the holding temperature and time. The fundamental information obtained contributes to building the database to predict the distribution of TiN in steel during the whole manufacturing process.

与以往的工作不同，系统研究了低合金元素浓度的 Fe-Al-Ti-O-N 合金在 1273 K 和 1573 等温保温过程中 TiN 的形状、尺寸分布、总数密度和分布特征的演变。 K. 保持时间从 0.5 到 12 小时不等。TiN 在每种合金中都是饱和的，并且在保温之前将其与氧化物分离。氮化钛 > 0.5 μm 通过自动 SEM-EDS 分析。结果表明，TiN的尺寸在各合金中均服从对数正态分布。热保持对TiN的长方体形状修改无效；它提高了合金晶界上大TiN的浓度。在任一保持温度下的热保持期间，TiN 的奥斯瓦尔德熟化在任何合金中都不明显。TiN的平均尺寸与保温时间的关系不符合LSW方程。热保持过程中TiN的尺寸分布受TiN过饱和度、合金中Ti/N摩尔比、铸态合金中TiN的原始分布以及保持温度和时间的综合影响。