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Title: Ammonia-treated phosphate glasses useful for sealing to metals metals

Abstract

A method of improving surface-dependent properties of phosphate glass such as durability and wear resistance without significantly affecting its thermal expansion coefficient is provided which comprises annealing the glass in a dry ammonia atmosphere at temperatures approximating the transition temperature of the glass. The ammonia annealing treatment of the present invention is carried out for a time sufficient to allow incorporation of a thin layer of nitrogen into the surface of the phosphate glass, and the treatment improves the durability of the glass without the reduction in the thermal expansion coefficient that has restricted the effectiveness of prior ammonia treatments. The improved phosphate glass resulting from this method is superior in wear resistance, yet maintains suitable thermal expansion properties so that it may be used effectively in a variety of applications requiring hermetic glass-metal seals.

Inventors:
 [1];  [2]
  1. Albuquerque, NM
  2. Rolla, MO
Issue Date:
Research Org.:
AT&T
OSTI Identifier:
867968
Patent Number(s):
5045508
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
C - CHEMISTRY C03 - GLASS C03C - CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUS ENAMELS
DOE Contract Number:  
AC04-76DP00789
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
ammonia-treated; phosphate; glasses; useful; sealing; metals; method; improving; surface-dependent; properties; glass; durability; wear; resistance; significantly; affecting; thermal; expansion; coefficient; provided; comprises; annealing; dry; ammonia; atmosphere; temperatures; approximating; transition; temperature; treatment; carried; time; sufficient; allow; incorporation; layer; nitrogen; surface; improves; reduction; restricted; effectiveness; prior; treatments; improved; resulting; superior; maintains; suitable; effectively; variety; applications; requiring; hermetic; glass-metal; seals; applications requiring; expansion coefficient; time sufficient; thermal expansion; phosphate glass; transition temperature; phosphate glasses; wear resistance; metal seal; significantly affecting; ammonia atmosphere; expansion properties; glass resulting; glasses useful; hermetic glass; metal seals; significantly affect; annealing treatment; /501/65/

Citation Formats

Brow, Richard K, and Day, Delbert E. Ammonia-treated phosphate glasses useful for sealing to metals metals. United States: N. p., 1991. Web.
Brow, Richard K, & Day, Delbert E. Ammonia-treated phosphate glasses useful for sealing to metals metals. United States.
Brow, Richard K, and Day, Delbert E. Tue . "Ammonia-treated phosphate glasses useful for sealing to metals metals". United States. https://www.osti.gov/servlets/purl/867968.
@article{osti_867968,
title = {Ammonia-treated phosphate glasses useful for sealing to metals metals},
author = {Brow, Richard K and Day, Delbert E},
abstractNote = {A method of improving surface-dependent properties of phosphate glass such as durability and wear resistance without significantly affecting its thermal expansion coefficient is provided which comprises annealing the glass in a dry ammonia atmosphere at temperatures approximating the transition temperature of the glass. The ammonia annealing treatment of the present invention is carried out for a time sufficient to allow incorporation of a thin layer of nitrogen into the surface of the phosphate glass, and the treatment improves the durability of the glass without the reduction in the thermal expansion coefficient that has restricted the effectiveness of prior ammonia treatments. The improved phosphate glass resulting from this method is superior in wear resistance, yet maintains suitable thermal expansion properties so that it may be used effectively in a variety of applications requiring hermetic glass-metal seals.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1991},
month = {1}
}