| 摘要 |
A riser for a mold includes a riser body formed of an exothermic material. A cavity is located in the riser body and is adapted to contain an associated molten metal. An opening is provided in the riser body for communicating the riser body cavity with a cavity of an associated mold. The riser body exothermic material consists essentially of a reactive mixture which includes, in weight percent, from about 25% to 65% silica, from about 5% to 18% sodium nitrate, from about 1% to 8% sodium hexafluorosilicate, from about 15% to 40% aluminum, and from about 2% to 20% iron oxide.
|
