Inclusion and Microstructure Characteristics in a Steel Sample with TiO2 Nanoparticle Addition and Mg Treatment
Inclusion and Microstructure Characteristics in a Steel Sample with TiO2 Nanoparticle Addition and Mg Treatment
复制标题
添加 TiO2 纳米粒子和镁处理的钢样品中的夹杂物和显微组织特征
DOI：
10.3390/met9020171
复制
发表时间：
2019-02-01
期刊：
影响因子：
2.9
通讯作者：
Kong, Hui
中科院分区：
文献类型：
--
作者：
Cai, Zhengyu;Kong, Hui
TiO2 nanoparticles and Mg alloy were added to molten steel in sequence to investigate the inclusion and microstructure characteristics. Compared with a non-treated sample, these additives resulted in the formation of Ti-Mg-bearing inclusions, which proves that the additives were valid. The size evolution from nanometer-scale TiO2 to micrometer-scale oxides hints at the agglomeration and growth of the TiO2 nanoparticles, which is due to the possible formation of a liquid-capillary force, the decomposition reaction of TiO2, and the higher Gibbs free energy of the nanoparticle. Furthermore, the statistical analysis of the oxides indicated that with the addition of the TiO2 nanoparticles and Mg alloy, the oxides were refined and their density was higher. Few pure MnS were observed in the treated sample. This is due to the fact that most oxides separated out in the liquid region at 1873 K based on the oxide composition and the calculated Al2O3-Ti3O5-MgO phase diagram. Thus, MnS preferred to segregate on them during solidification. After etching, it was found that the Ti-Mg-bearing oxide can induce the nucleation of intragranular acicular ferrites. The appearance of these acicular ferrites was not observed in the non-treated sample. This comparison indicates the effectiveness of the external adding method in oxide metallurgy.
