Method for forming complex ceramic shapes
OwnerCurtis E. Scott, Douglas G. Seredich +3inventors
InventorsCurtis E. Scott, Douglas G. Seredich, Daniel Polis, Vishal Gauri, Karthik Sivaraman
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Abstract
A method for forming single element arc tubes is provided. The method includes the use of the lost foam process in combination with ceramic forming processes. First, a polymeric material (20) is formed to define the internal dimensions. The outer dimensions are established with an external mold (40), followed by filling the mold with a suspension (60) that hardens. The outer mold is removed and the part is debindered to melt and remove the inner foam shape, followed by sintering to form a substantially transparent ceramic arc tube (70).
Claims23
A method of forming a single element arc tube (70) for a ceramic metal halide lamp comprising the steps of:
- providing an inner form (20) having an external conformation that matches a desired internal dimensions of an arc tube;
- providing an outer form (40) around the inner form and defining a cavity (50) therebetween;
- filling the cavity with a suspension (60) that subsequently hardens;
- and
- removing the inner and outer forms.
A ceramic arc tube formed by a process including the steps of:
- providing an inner core (20) formed of a carbonaceous material having an external conformation that matches desired internal dimensions of the arc tube;
- gelcasting an alumina suspension around the core;
- debindering the alumina suspension;
- degrading the inner core at an elevated temperature;
- and
- sintering the arc tube.
Dependencies are inferred from the claim text.