METHOD FOR PREVENTING DEVELOPMENT OF MICROCRACK IN HIGH NI ALLOY STEEL CONTINUOUS CAST SLAB

摘要

PURPOSE:To prevent microcrack and to obtain a sound high Ni alloy steel continuously cast slab by specifying the producing condition at the time of producing the continuously cast slab of high Ni alloy steel containing the limited compositions of Ni and Cr in iron. CONSTITUTION:At the time of producing the continuously cast slab of high Ni alloy steel containing 20-50wt.% Ni and 6.5wt.% Cr in the iron, mold powder having 1.4-2.0 poise viscosity at 1300 deg.C is used and further, negative strip time deciding number of oscillation to a mold, stroke and casting velocity, is controlled to =0.35sec to execute the continuous casting and the spray water flow rate in spray cooling zone positioned at lower part of the mold us controlled to =0.7kg steel.