摘要 |
foundry. SUBSTANCE: method of coating application to ceramic parts includes application of coating layer by layer. In this case, internal and external layers are applied from alumino-chromo-phosphate binding agent, and intermediate layer from alumino-chromo-phosphate binding agent and aluminum oxide. Internal and external layers of coating are applied in amount ensuring surface density of 0.05-0.20 kg/sq.m, and intermediate layer in amount ensuring surface density of 0.12-0.35 kg/sq.m. Each layer of coating is dried at room temperature and subjected to three-stage heat treatment. At the first stage, temperature is elevated from room one to 100-150 C and held at this temperature form 60-90 min. At the second stage, temperature is elevated to 150-250 C and held at this temperature for 50-60 min. At the third stage, temperature is elevated up to 250-360 C and held at this temperature for 30-60 min. Invention provides for improvement of mold quality and chemical composition and structure of coatings. EFFECT: higher efficiency. 3 cl, 1 tbl
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