| 摘要 |
PURPOSE: A CGI cast iron and a preparation method thereof are provided to adjust the quantity of magnesium precisely and control the quantity of copper and tin so as to obtain CGI cast iron having a tensile strength of 500~600 MPa, a yield strength of 350~450MPa, and Brinell hardness of 255~280. CONSTITUTION: A CGI case iron preparation method comprises the next step. A cast iron material containing sulfur of 0~0.02 weight%, carbon of 3.65~3.75 weight%, silicon of 2.0~2.25 weight%, manganese of 0.3~0.6 weight%, phosphorus of 0~0.04 weight%, and residual Fe is molten in a blast furnace(100) to obtain a molten cast iron. Copper of 1.2~1.4 weight%, tin of 0.07~0.10 weight%, and magnesium of 0.008~0.018 weight% are put in a ladle(200). The molten cast iron is discharged into the ladle to prepare a cast iron molten solution(110). The magnesium contained included in the cast iron molten solution contained in the ladle is grasped to determine the quantity of magnesium to be added. Magnesium of the determined quantity is added to the cast iron molten solution contained in the ladle. The cast iron molten solution having magnesium added thereto is injected into a mold(400). |
