HARDENER FOR CASTING SOLUBLE GLASS Russian patent published in 2021 - IPC B22C1/18 

FIELD: manufacturing of molds and rods for metal casting.

SUBSTANCE: hardener for casting soluble glass, then—hardener, includes ester, alcohol and amorphous silicon dioxide obtained by thermal decomposition of ZrSiO₄; wherein 100 parts by weight of hardener include 35–65 pbw of ester, 13–20 pbw of alcohol, 20–45 pbw amorphous silicon dioxide. Curing agent preparation method involves the following stages: (1) first adding an ester weighted in accordance with said weight ratio into a high-speed mixer stirring tank and mixing thereof; (2) adding alcohol suspended in accordance with said weight ratio; (3) maintaining stirring speed at 800 rpm or more, adding amorphous silicon dioxide, weighted in accordance with said weight ratio, and continuously stirring for 10–20 minutes to obtain a suspension as a curing agent. Hardener is used to produce a sand mold or a casting rod, wherein the sand mold or casting rod is used for metal casting, preferably for steel casting. Self-curing sand from soluble glass, in which 100 pbw of total weight of said sand includes 95–98 pbw of quartz sand, 1.8–3.6 pbw of soluble glass and 0.2–1.4 pbw curing agent.

EFFECT: hardener has adhesion-enhancing effect, long storage life and ease of use.

7 cl, 2 tbl, 11 ex