| 摘要 |
FIELD: foundry; casting of magnesium alloys. SUBSTANCE: proposed parting additive for molding sand includes boric acid, 13-17 mass-%; crystalline hydrate of magnesium, 14-25 mass-% and the remainder being carbamide. Additive may additionally contain crystalline hydrate of aluminum sulfate, 4-8 mass-%; or one agent from group containing ammonium sulfate, potassium tetraborate or potassium tetrafluoroborate, 1-6 mass-%. Additive may also additionally contain crystalline hydrate of aluminum sulfate, 4-8 mass-% and one agent from group containing ammonium sulfate , potassium tetraborate and potassium tetrafluoroborate, 1-6 mass- %. EFFECT: improved parting and protective properties of additive. 4 cl, 2 tbl |
