2025 Fan TWIP Alloy Inclusions Solidification

Non-metallic inclusions significantly impact the performance of steel, especially regarding precipitation control during the solidification of high Mn and Al TWIP steel. This study investigates the effects of Al and N contents on the characteristics of non-metallic inclusions and their precipitation behaviors in unidirectionally solidified Fe-Mn-C-Al TWIP alloys. Utilizing thermodynamic analysis, the research findings demonstrate that increasing the initial concentrations of Al and N promotes their mutual segregation and increases AlN particle size. The results indicate that the influence of N content on AlN precipitation is more pronounced than that of Al content, leading to a decrease in the critical supersaturation needed to initiate precipitation. Conversely, Al content more significantly impacts AlON precipitation. In conditions with consistent oxygen levels, a rise in Al concentration alters the primary bonding with oxygen atoms, which reduces aO in the melt, thereby rendering changes in N content the main factor affecting AlN precipitation. The study highlights the critical role of regulatory alloy components in managing non-metallic inclusions during solidification in TWIP steel.