Comparison between precipitation kinetics of manganese sulfide during hot compression process with one and two holding time in grain-oriented electrical steel

Abstract
The aim of this work is the study of manganese sulfide particles precipitation (Fe-3%Si) after one and two holding time during hot compression process. Samples were heated at 1573K for 1800s. After the specimens were cooled down to 1373 and 1173K, hold for 32, 60 and 338s and the compression of 50% is applied during the holding time and then water quenched, in the process with two holding time, the first holding time is 60s (50% is applied), then the compression of 30% is applied (second holding time : 32, 60 and 338s), then water quenched. Grain size characterization was carried out using OM. The study of comparison precipitation has been carried out on the surface and the center of each sample. For TEM characterization of MnS particles an extraction replica technique has been used. Image analyzer measured the particle diameter. Optical micrographs showed that the grain size decreases with the second holding time process for the two temperatures on the two studied regions. Hot compression process with two holding time provides more dislocation and defects increasing the possibility of MnS particles precipitate and providing higher MnS particle density.