摘要 |
PROBLEM TO BE SOLVED: To improve pickling property and to impart an excellent surface quality free from a defect by applying finish rolling specifying a max draft to a stainless steel plate to make surface scale a specified thickness after descaling the plate by injecting a specified high pressure water spray on the sheet bar surface in which a collision pressure and a flow rate density are specified. SOLUTION: A stainless steel slab having a composition containing >=10 wt.% Cr, preferably about <=30 wt.% is applied to hot rough rolling to make a sheet bar. On this sheet bar surface, high pressure water spray having a collision pressure of >=25 kgf/cm<2> per a unit spray area is injected by making a flow rate density to >=0.002 l/cm<2> and descaling is conducted. Successively, finish rolling in which a max draft R(%) per one pass satisfies a formula, R<=-0.9 A+54, (A:Cr content (wt.%) of the slab), is applied so that a surface scale thickness is made to <=2.5μm. At this time, a temp. of finish rolling completion is preferably about >=950 deg.C for an austenitic steel and about >=700 deg.C for a ferritic steel.
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