| 摘要 |
FIELD: metallurgical industry branch. ^ SUBSTANCE: sand contains aluminum-chrome phosphate binder modified at synthesis stage with methyl carbamides taken in quantity 0.6 -1.10 mass. %, amine based modifying agent and refractory filler. Modifying agent contains, mass. %: monoethanol amine, 15 - 70; 1-(2oxyethyl)imidazolidone-2 mixed with and 1-(2-oxyethel)ethylene diamine, no more than 50; water, no more than 20. Ingredients of sand are taken in next relation, mass. %: binder, 2 - 6; amine based modifying agent, 0.2 - 3.0; refractory filler, the balance. ^ EFFECT: enhanced preservation properties, lowered tendency for crumbling, stable strength characteristics even after setting. ^ 2 tbl |
