| 摘要 |
PURPOSE: Provided is a manufacturing method of siliceous slit type nozzle used for production of amorphous alloy at high temperature by direct coagulation casting unlike conventional slip casting. CONSTITUTION: The manufacturing method of siliceous slit type nozzle is as follows: preparing a silica sol by dispersing ultrafine fumed amorphous silica powder into water, wherein the fumed silica has 20-300m¬2/g of surface area and 7-100nm of size; re-dispersing the slurry(sol) by adding a strong alkali solution including NH3 ion, such as tetramethylammonium hydroxide(TMAH) and tetraethylammonium hydroxide(TEAH), to be the sol more than pH10; adding coagulator, pH reducer, such as methyl formate, ethyl lactate, or formamide to be the silica slurry under pH9.5; pouring the slurry into a mold for coagulation(gelation); drying formed siliceous nozzles, calcining at 900deg.C and sintering at 1000-1400deg.C.
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