Non-consumable tungsten electrode for arc welding in inert gas - where only the electrode tip contains addn. increasing electron emission

摘要

The electrode is made of refractory material, esp. tungsten, and consists of a shaft free from addns. (a) employed to increase electron emission; on one or both ends of the shaft is a tip attached by welding; and the tip has a higher electron emission than the shaft. The pref. shaft is made of tungsten, whereas the tip is pref. tungsten contg. an addn. (a), esp. 0.2-10 wt. % ThO2. The shaft and the tip are pref. made separately by powder metallurgy, and the tip is possibly shaped by hot working. The shaft and tip are then joined by either electron beam welding, or pulsed arc welding with brief application of pressure. The tip may then be ground. Simple mfr. of an electrode contg. addn. (a) only in the tip, and with long working lift is TIG or plasma welding is provided.