汽车用铸态高韧性中小球铁铸件的试验研究

Experimental Research of As-cast High Toughness Ductile Iron for Truck

采用中频感应电炉熔炼获得了高温、低硫、低氧化的优质铁液。合理地设计了铁液化学成分，选用低稀土低镁FeSiMg6RE2球化剂进行盖包法球化处理，用含Ba的多元微量复合孕育剂进行孕育处理，稳定生产出了铸态高韧性QT450-18球铁。结果表明，铸件本体的抗拉强度达到456．3-500．6MPa，伸长率达到18．4％-19．2％。

The quality molten iron of high temperature, low sulfur and low oxidation was obtained by medium frequency induction furnace smelting. The chemical composition of molten iron was designed reasonably. The tundish-cover nodulizing process was conducted by using low rare earth magnesium nodulizing agent FeSiMg6RE2. The inoculation was conducted by using multiple trace compound inoculant with Ba. As-cast high toughness QT450-18 ductile iron was steadily produced. The results show that, the tensile strength of casting body reaches 456.3 -500.6 MPa and elongation reaches 18.4% -19.2%.