| 摘要 |
PURPOSE:To obtain hot rolled steel products free from surface flaws by forming the films of Ni-containing coating material in the form of fine powder imparted with a self-exothermic property by air spraying on the surfaces of a high-temp. steel slab contg. Cu and Sn at respectively specific ratios to a specific thickness and hot rolling this slab. CONSTITUTION:The Ni-containing coating material 2 in the form of the fine powder imparted with the self-exothermic property is sprayed to the surfaces of the high-temp. steel slab contg. >=0.3% Cu and >=0.01% Sn to form the films at 2 to 30mum thickness. This slab is then hot rolled. The fine powder of the compounded Ni-containing coating material 2 is blown at a specified rate per minute from the air spray guns 5 arrayed right under a continuous casting mold to coat both surfaces of the ordinary steel slab at a prescribed thickness; thereafter, the slab is passed through a heating furnace and is hot rolled. As a result, the Ni-containing coating material imparted with the self-exothermic property is air sprayed and, therefore, the defectless hot rolled products free from the surface flaws are produced without making a big equipment investment but only by using an extremely small amt. of expensive Ni even with the tramp element-contg. steel. |
