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How are uranium dioxide pellets made for light-water reactor fuel?
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uranium processing
How uranium is enriched to make a nuclear weapon.
To produce uranium dioxide (UO₂) pellets for light-water reactors, manufacturers follow a precise ceramic fabrication process:12
- Preparation: Enriched UO₂ powder is ground to a fine, flourlike consistency. Appropriate quantities of enriched, natural, or depleted powders are blended together.12
- Compaction: An organic binder is added to the powder to assist in the process. The mixture is then inserted into a die and mechanically pressed into a pellet shape, typically measuring approximately 6 mm in diameter and 10 mm in length.12
- Sintering: The pellets are heated to burn off the organic binder and then sintered in a furnace at high temperatures, ranging from 1,500 to 1,800 °C (approximately 2,700–3,300 °F). This firing process creates a dense ceramic pellet, reaching about 95 percent of its theoretical density.12
Once formed, these pellets are loaded into zirconium alloy cladding tubes, which are then filled with an inert gas and welded shut to create fuel rods.12