Migration Behavior Of Inclusions In Steel Liquid Coagulation Interface In Oxide Metallurgy

The oxide metallurgy process uses Mg-Al-Ti-type inclusions to induce IAF to improve the toughness of steel.The distribution of inclusions has an important role in induced IAF,and the migration behavior of inclusions has an important impact on the distribution of the clip.By high-temperature solidification experiment,the migration behavior of the inclusions on the solidification interface is studied by optical microscope and electron microscope equipment,providing theoretical basis for regulating the distribution of inclusions in solid solidification tissue.Experimental steel using oxide metallurgical techniques was used in the induction heating furnace,and under different sensing current power operating conditions,the experimental steel in the furnace was integrated into the solidification process,and "beneficial" inclusions flow along with the steel liquid phase Aggregation behavior is studied.The study found that the larger the liquid phase flow intensity in the steel liquid,the easier the inclusions,the easier of the coagulation end.In the process of solidification,as the fluid phase flow intensity is limited,"beneficial" inclusions are easily aggregated at the end of the coagulation,the larger the chance of induced the needle ferrite in the Aushuric crystal,so the needle-shaped ferrite The volume fraction gradually increases in the process of the steel liquid from the start of solidification to the end solidification.Studies have shown that MnS is easily attached to the composite inclusions and can be used to characterize the migration behavior of the clutch coagulation front edge.First,thermodynamic calculations for MnS,The results show that MnS is easily attached to Mg Al2O4 and Si O2 Al2O3 during the precipitation of solid-liquid two-phase district.Through high temperature coagulation orthogonal experiment,the scanning electron microscope is used to statistically,When the inclusion is attached to the MNS area of less than 0.2 μm 2,the inclusions are easily captured in front of the coagulation,enters the austenite crystal,easy to induce the needle ferrite;When the edge of the clip is more than0.3 μm 2,the inclusions are gathered at the end solidification position,and it is not easy to enter the Aushuric crystal.By varying analysis,MNS content,cooling rate,insulation temperature on the influence of MNS adhering to inclusions.The migration behavior of the clip of the coagulation front edge is observed using a high temperature laser confocal microscope,and the magnetic field changes the liquid phase flow to analyze the movement trajectory of the inclusion interface.Studies have found that inclusions have a negative acceleration process when inclination is close to solidification.Missing liquid phase flow,inclusion movement speed is significantly reduced,and inclusions are more likely to enter the coagulation proof.Further analysis of the stress of inclusions in the coagulation front edge indicates that migration behavior of inclusions is divided into attraction,exclusion and no effects of 3 cases.The liquid phase flow rate can be slowed,and in the first case,the inclusion is the effective distance of the coagulation front edge capture.Figure 52;Table 17;Reference 68 articles.