Thermodynamic Research of MnS Precipitation in the Process of the Slab Continuous Cast

摘要

The article made use of thermo-calc thermodynamic software simulating the solidification process of AH32.Through the thermodynamic calculation,we can draw the conclusion that most of MnS inclusions are precipitated below the solidificational temperature as the result of the enrichment of manganese and sulfide in the grain boundary.The morphology of MnS was observed by using SEM of QUANT-400,we can concluded that 1/4 zone in the thickness direction of the slab was the key position of MnS precipitation,which are the major reason of the crack of slab.Through the measures of Calcium handling and Electromagnetic stirring in the steel making process,the middle crack defects have been improved obviously.