GAS DISCHARGE LAMP FOIL WELDED TO CURRENT LEAD WITH IRON OR IRON ALLOY

摘要

Electric lamp having a hermetically sealed gas-filled hard-glass or vitreous-silica lamp envelope provided with a current lead-in which is sealed into a portion of the lamp envelope and comprises a foil mainly consisting of molybdenum and a current supply lead mainly consisting of tungsten which is secured to the foil by a welded joint and extends into the lamp envelope. The welded joint contains iron or an alloy of at least 50% by weight of iron and one or more of the elements scandium, titanium, vanadium, chromium, manganese, cobalt, nickel and copper as the welding agent.