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Title: Tungsten wire for incandescent lamps

Abstract

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.

Authors:
;  [1]
  1. (General Electric Corporate Research and Development, Schenectady, NY (USA))
Publication Date:
OSTI Identifier:
6450145
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Materials Research; (USA); Journal Volume: 5:9
Country of Publication:
United States
Language:
English
Subject:
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

Citation Formats

Walter, J.L., and Briant, C.L. Tungsten wire for incandescent lamps. United States: N. p., 1990. Web. doi:10.1557/JMR.1990.2004.
Walter, J.L., & Briant, C.L. Tungsten wire for incandescent lamps. United States. doi:10.1557/JMR.1990.2004.
Walter, J.L., and Briant, C.L. Sat . "Tungsten wire for incandescent lamps". United States. doi:10.1557/JMR.1990.2004.
@article{osti_6450145,
title = {Tungsten wire for incandescent lamps},
author = {Walter, J.L. and Briant, C.L.},
abstractNote = {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.},
doi = {10.1557/JMR.1990.2004},
journal = {Journal of Materials Research; (USA)},
number = ,
volume = 5:9,
place = {United States},
year = {Sat Sep 01 00:00:00 EDT 1990},
month = {Sat Sep 01 00:00:00 EDT 1990}
}
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