There is no need to decontaminate the outside of the container.
Figure 1 depicts the process stages. In its initial double-wall form, the volume between the walls is isolated from the environment; in other words, the outer wall (which is later sacrificed) initially serves to protect the inner container from contamination. The sample is placed inside the container through an opening at one end, then the container is placed into a transfer dock/lid. The surfaces that will be welded together under the explosive have been coated with a soft metallic sacrificial layer (see Figure 2). During the explosion, the sacrificial layer is ejected, and the container walls are welded together, creating a strong metallic seal. The inner container is released during the same event and enters the clean environment.
This work was done by Benjamin Dolgin and Joseph Sanok of Caltech for NASA's Jet Propulsion Laboratory. For further information, access the Technical Support Package (TSP) free on-line at www.techbriefs.com/tsp under the Manufacturing category. NPO-20868.
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