Protective coating for inhibiting platinum bushing from being oxidized and volatilized, and manufacturing method and application thereof

Abstract

The invention discloses a protective coating for inhibiting a platinum bushing from being oxidized and volatilized and reducing the loss of noble metals, a preparation process and application. The protective coating mainly comprises the following components in percentage by weight: 20 to 50 percent of silicon oxide, 20 to 45 percent of aluminum oxide, 5 to 15 percent of sodium silicate and 10 to 25 percent of sodium tetraborate. The protective coating can prevent platinum and rhodium alloys from being oxidized and volatilized at high temperature effectively, and compared with the bushings which are not processed, the bushing which is processed by a coating process can reduce the loss amount by over 30 percent.

Description

technical field [0001] The invention relates to the field of glass fiber technology, in particular to a method for protecting bushings in the glass fiber industry, in particular to a protective coating for suppressing oxidation and volatilization on the surface of platinum bushings and reducing loss of precious metals, as well as its preparation process and application. Background technique [0002] Platinum rhodium has a high melting point, stable chemical properties, can withstand rapid cooling and heat, and has good processing and welding properties. The bushing plate made of platinum rhodium alloy is a standard material for the glass fiber industry. The operating temperature of the platinum-rhodium alloy bushing (platinum bushing for short) is between 1100°C and 1300°C, and the platinum on the outer surface is easily oxidized to PtO 2 , while PtO 2 It is in the form of a thin solid surface film at a lower temperature, which has a certain protective effect on the leakage...

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Problems solved by technology

[0003] In terms of reducing the use loss of platinum slats, in the prior art reports, "Casting slat coating" contributed by Ma Mingjie provides an anti-oxidation coating formulated with alumina coating powder and an appropriate amount of binder. method, the protection effect of this method is relatively poor, the coating after high temperature sintering is very easy to crack, and the coating is easy to fall off during the pouring process, the cracked part of the bushing plate cannot heal itself during use, and the volatilization in some areas still cannot get better. protection of

[0004] In addition, the Chinese patent application CN101638294A discloses "a coating for reducing the use loss of platinum bushings and its preparation method", which is prepared from coating powder made of aluminum oxide, silicon oxide, and sodium oxide, Suzhou soil, and distilled water. The process cycle is long; the bushing plate after high temperature sintering will be slightly deformed; the sintered coating has low impact resistance and is easy to fall off during the later pouring process

[0005] Therefore, the existing protective coatings cannot really reduce the use loss of platinum, and cannot form a good protection for the platinum bushing

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