H. Cross Company is one of the largest suppliers of elliptically shaped etched molybdenum foil for hermetic sealing of quartz lamps.
Etched molybdenum foil, of all metals, is used since its coefficient of expansion is the closest to quartz. The elliptical shape produces an air and gas tight lead into the lamp envelope, thus preventing filament degradation during lamp operation.
|Ribbon||Thickness||.0005″ to .004″|
|Width||.030″ to. 945″|
Etched foil leads are welded assemblies used as the lead wires in many types of hard glass or quartz encapsulated devices for high temperature applications. They provide the functions of internal and external electrical connection and mechanical support, plus a hermetic sealing capability for pinch seals. Applications include mercury arc lamps, tungsten-halogen cycle lamps, infrared heat lamps, and certain electronic and instrumentation applications.
H. Cross Company starts with a very tightly controlled molybdenum wire made to our own specifications free from inclusions, splits, or contaminations. It is then rolled very thin without creating pin holes or leaker lines.
After rolling, the material is electrolytically etched, again under stringent controls, to arrive at the elliptical shape with the proper thickness and width to special requirements of each customer. It is then cleaned, annealed, inspected and spooled for shipment. For best protection of the sharp edges, the spools of H. Cross Company design are slightly wider than the ribbon.