PREPARATION STUDY OF SEMI-SOLID 60Si2Mn SPRING STEEL SLURRY

The nondendritic semi-solid slurry preparation of 60Si2Mn spring steel is studied in this paper. The experiments show that when stirred for 2 minutes under the test condition, the semi-solid slurry with 50%-60% fraction solid phase and spherical primary austenite in the size of 100-300μm can be obtained and is easy to be discharged from the little bottom hole of the stirring chamber. The more homogeneous temperature field and solute distribution of the 60Si2Mn spring steel melt appear because of the electromagnetic stirring, which restrains the formation of large primary austenitic dendrites and create a base to form spheroidized structure. The stronger temperature fluctuation in the melt with many rosette primary austenites caused by stirring and the remelting of the secondary arm roots in the same time are the most important reasons for deposition of spheroidized primary austenites.