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Separating electroformed Ni replica from mandrel

adv.  

We are electroforming (parabolic plus hyperbolic) i.e. replicating, cylindrical shells which will be assembled into grazing incidence X-ray telescopes for astronomical research.(One-half of the 2002 Nobel prize in physics was awarded to a researcher in this area) There is an established technique for producing a layer of gold, which is an efficient reflector of X-rays below 8 keV on the interior reflecting surface of the cylinders by first evaporating gold on the mandrel and having it naturally transferred to the electroformed replica during separation. The gold has the dual role of facilitating the separation process and acting as the reflecting material.

Our next goal is to extend the energy range by substituting a tungsten-silicon multi layer for the gold because gold is not desirable at higher energies. Does anyone know of a low atomic number material that like W, Si,Au is smooth on a microscopic scale than can act as a We are electroforming (parabolic plus hyperbolic) i.e. replicating, cylindrical shells which will be assembled into grazing incidence X-ray telescopes for astronomical research.(One-half of the 2002 Nobel prize in physics was awarded to a researcher in this area) There is an established technique for producing a layer of gold, which is an efficient reflector of X-rays below 8 keV on the interior reflecting surface of the cylinders by first evaporating gold on the mandrel and having it naturally transferred to the electroformed replica during separation. The gold has the dual role of facilitating the separation process and acting as the reflecting material.

Our next goal is to extend the energy range by substituting a tungsten-silicon multi layer for the gold because gold is not desirable at higher energies separation agent? The sequence would then become: (1) deposit the separation agent on the mandrel, (2) sputter the multi layer, (3)electroform the replica over the multi layer, (4) remove the replica which now has either the multi layer or the low atomic number material on the interior reflecting surface. The separation agent can either remain on the replica if it is low atomic number, or be easily removed leaving the multi layer, or remain on the mandrel. Several variations are possible as long as the multi layer or the multi layer with a low atomic surface layer covers the interior surface of the replica at the end.

We would appreciate any suggestions that anyone can propose we try.

Paul Gorenstein
- Cambridge, Massachusetts
2002