Coating composition for preventing high temperature oxidation for electrodes
Abstract
Abstract The invention relates to a coating composition containing ceramic components, for preventing high temperature oxidation of graphite electrodes employed in electric furnace steelmaking. This ceramic composition consists of the following components: (a) 40-75% by weight of silicon carbide as a heat radiation component; (b) 15-40% by weight of a binding and heat radiation promoting component consisting of 3-20 parts by weight of silicon nitride, 5-20 parts by weight of salt of phosphorous-containing acid, 2-10 parts by weight of chromium oxide, 2-10 parts by weight of tantalum carbide, and 5-20 parts by weight of pulverous aluminum; (c) 10-35% by weight of an additive for improving the adhesion to the graphite electrode and increasing the binding strength between the coated layers, consisting of 1-10 parts by weight of aluminum oxide, 3-15 parts by weight of glass powder, 3-15 parts by weight of zirconium oxide, 1-10 parts by weight of silicon dioxide, 1-10 parts by weight of magnesium oxide, and 1-10 parts by weight of iron oxide; (d) 5-20% by weight of a metal powder consisting of 0-40 parts by weight of pulverous copper, 0-40 parts by weight of pulverous nickel, 0-40 parts by weight of pulverous stainless steel, 0-40 parts by weight of pulverous iron, and 0-40 parts by weight of pulverous tin; (e) 2-5% by weight of a sintering promoter mixture consisting of 10-30 parts by weight of silver carbonate, and 30-50 parts by weight of copper sulfate, and/or 30-50 parts by weight of iron sulfate; and (f) 3-7% by weight of a melting point lowering component consisting of 30-60 parts by weight of iron fluoride, and 40-70 parts by weight of copper fluoride.
Inventors
- 👤 Kazutomi Funahashi
- 👤 Koichi Yoshii
- 👤 Yoichi Nakamura
- 👤 Tatsumi Oshikiri
- 👤 Hajime Kobayashi
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1990-05-25 | 1990-11-24 | 1991-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-25 | 1994-11-24 | 1995-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-25 | 1998-11-24 | 1999-05-26 | $7700.00 | Window Closed / Lapsed |