Tungsten wire for incandescent lamps

Journal Article · Sat Sep 01 00:00:00 EDT 1990 · Journal of Materials Research; (USA)

DOI:https://doi.org/10.1557/JMR.1990.2004· OSTI ID:6450145

Walter, J L; Briant, C L ^[1]

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1. General Electric Corporate Research and Development, Schenectady, NY (USA)

Tungsten wire for incandescent lamp filaments must operate at high temperatures and for long times. To meet these requirements, the grain morphology of the wire must be controlled to reduce the propensity for grain boundary sliding. The morphology is a function of the distribution of very small pockets of potassium in the wire and the mechanical processing from ingot to wire. The behavior of the filament is directly related to the grain morphology. This paper describes the mechanism by which the potassium is incorporated into and distributed in the ingot. The elongation and spheroidization of the bubbles during hot rolling and swaging is also examined and related to the grain morphology of wire. Some indications of the relationship between grain morphology and filament behavior are also given.

• OSTI ID: 6450145
• Journal Information: Journal of Materials Research; (USA), Vol. 5:9; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
LIGHT BULBS
FILAMENTS
TUNGSTEN
CRYSTAL DOPING
GRAIN BOUNDARIES
BUBBLES
GRAIN SIZE
MICROSTRUCTURE
MORPHOLOGY
OPERATION
POTASSIUM
ROLLING
SWAGING
ALKALI METALS
CRYSTAL STRUCTURE
ELEMENTS
FABRICATION
MATERIALS WORKING
METALS
SIZE
TRANSITION ELEMENTS
360102* - Metals & Alloys- Structure & Phase Studies