Answers are grounded in this paper and cite their sources.
The acicular ferrite (AF) formation behaviors of submerged arc weld metals with various Al/O ratios and Mn contents were investigated. The nucleation sites of AF consisted of inclusions surrounded by a TiO layer. The Al/O ratio affected the number of inclusions that acted as AF nucleation sites. At high Al/O ratios, the number of inclusions was low and the microstructure was coarse.
No takes yet. Share an insight, caveat, or question.
Fujiyama et al. (2021) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: