MANUFACTURE OF STEEL PLATE EXCELLENT IN LASER CUTTING PROPERTY

• Main Authors: KAIZU TORU, KABASAWA MAKOTO, KOBAYASHI SATOO, OMURA MASAKI, URABE TOSHIAKI
• Format: Patent
• Language: English
• Published: 16.06.1998
• Edition: 6
• Subjects: CHEMISTRY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; PERFORMING OPERATIONS; PUNCHING METAL; ROLLING OF METAL; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a method for manufacture of a steel plate capable of high speed cutting while maintaining excellent cutting quality at the time of laser cutting for a hot rolled steel plate for use in a steel structure. SOLUTION: This steel plate excellent in laser cutting property is produced by performing descaling before or during rolling at the time of hot rolling of a steel plate, regulating final reduction of area (R) at finish rolling and finish rolling temp. (FT) to 5-25% and 950-650 deg.C, respectively, and also regulating cooling rate(CR) directly after finish rolling and coiling temp.(CT) to (5 to 60) deg.C/s and 550-250 deg.C. It is further desirable to perform, within the above manufacturing conditions, hot rolling under the conditions satisfying inequality FT×(1-R/100)×(7.5FT-4.5CR-13.5Cr.CT+1800CT)<=4.40×10 .