摘要 |
Physical vapor deposition techniques are used to coat fine particulates suspended in a fluidization gas. In one embodiment, an electron beam is directed toward a target comprising a coating material to generate a vapor of the material which is subjected to a flow of carrier gas. The resultant directional physical vapor deposition cloud is introduced into a fluidized bed chamber which contains fine powder particulates to be coated suspended in the fluidization gas. As the directional vapor cloud passes through the fluidized bed, the suspended particulates are coated with the coating material. The fluidized bed may comprise a recirculating or non-recirculating fluidized bed. The system may be used to produce substantially unagglomerated fine powders having many different types of coatings.
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