| 配方类型： |
EMULSIONS & DISPERSIONS |
| 配方说明： |
Boron Nitride Dispersion |
| 配方组成： |
"Baymal"/7
Water and Additives/75
Boron Nitride (Graphitic Form)/18 |
| 配制方法： |
In a one-quart blender is placed 370 ml of water, and with slow stirring, 35 g of "Baymal" colloidal alumina is added. Then 14 ml of 0.5 molar solution of barium acetate is added and stirring continued at high speed for two minutes.
At this point 90 g of bulky, flake-like boron nitride is added, stirred in at slow speed, then blended at high speed for one minute.
This mixture is very foamy. The foam will collapse on standing for a day or so, but addition of one drop of silicone-type antifoam agent will speed the removal of air, especially if the mixture is subjected to vacuum.
Addition of one gram of a nonionic wetting agent will improve spreading and adhesion of this composition on some surfaces.
The most noticeable characteristic of the dried film is its lubricity.
The colloidal alumina bonds this lubricant into a coating and makes it more durable, especially at higher temperatures.
The coating becomes water resistant when baked at 350'C for an hour, or at 450'C for a few minut |
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