METHOD AND APPARATUS FOR CONTINUOUSLY CASTING METAL

• Main Authors: YAMANE HIROSHI, BESSHO NAGAYASU
• Format: Patent
• Language: English
• Published: 19.12.2000
• Edition: 7
• Subjects: CASTING; CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES; PERFORMING OPERATIONS; POWDER METALLURGY; TRANSPORTING

PROBLEM TO BE SOLVED: To reduce the defects on the surface and in the inner part of a cast slab by impressing DC magnetic field to molten metal in a mold and casting while impressing ultrasonic wave to the mold and/or the cast slab at the outlet side. SOLUTION: The DC magnetic field is impressed to the molten steel (molten metal) 10 in the mold (mold for continuous casting, mold steel plate) 1 with a DC electromagnet 13. The ultrasonic wave is impressed to the mold 1 with an ultrasonic wave horn (ultrasonic generator) 14. The fluidity of the molten metal surface (molten steel surface) 7 is reduced with the DC magnetic field to restrain the entrapment of solid powder 5 and molten powder 6, and the lowering stream speed is reduced to shallow the invading depth of an inclusion 11 and a bubble 12. The quick stream speed is kept in the interface between a solidified shell (cast slab) 9 and the molten steel (molten metal) 10 with the ultrasonic wave to prevent the catching of the inclusion 11 and the bubble 12 into the solidified shell (cast slab) 9. It is desirable that the intensity of the DC magnetic field is 0.05-0.8 T at the center in the mold thickness direction and the frequency and the amplitude of the ultrasonic wave are 10-100 kHz and 1-15 μm, respectively.