| 摘要 |
PURPOSE:To form a copper mold for continuous casting of steel as a slowly cooled casting mold by working vertical grooves by chemical etching to a specified thickness or above of the Ni plating layer on the inside wall surface of said mold and subjecting the surface including such vertical grooves to 1 or >=2 kinds of Ni-P plating and Cr plating to a specific thickness or above. CONSTITUTION:The Ni plating layer having >=500mum thickness is provided on the inside wall surface of the copper mold for continuous casting of steel by an electroplating method using a sulfuric acid bath. The plating layer is chemically etched by an FeCl3 soln., by which the suitable grooves, for example, the grooves sized 280mum depth and 50mum wide are formed thereon. The surface thereof is subjected to 1 or >=2 kinds of the Ni-P plating and Cr plating to >=20mum by electroplating. The depth of the grooves is, for example, 280mum to 270mum in this case and the shape of the grooves changes hardly. The suitable groove depth is therefore maintained even after a surface treatment, by which the slow cooling effect of the mold is improved and the surface characteristic of an ingot is improved as well. |
