Water-Cooling Method of Steel Material and Steel Material Obtained by That Water-Cooling Method

摘要

The oxide film thickness of the steel material surface (dH2O+do2) is made to become 15 nm or less where post-treatment after water-cooling is not needed by suitably setting the conditions of the water-cooling start temperature (Ti), water-cooling end temperature (To), steel material thickness (d), concentration of solute oxygen in the cooling water (Do), and cooling rate (CR) in the equation of dH2O+do2=7.98x10-4(Ti-To)dDo+{5.50x10-3(Ti2-To2)-6.51 (Ti-To)}/CR.