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Title: Nondestructive method for chemically machining crucibles or molds from their enclosed ingots and castings

Abstract

An inventive method is described for chemically machining rhenium, rhenium and tungsten alloy, and group 5b and 6b crucibles or molds from included ingots and castings comprised of oxide crystals including YAG and YAG based crystals, garnets, corundum crystals, and ceramic oxides. A mixture of potassium hydroxide and 15 to 90 weight percent of potassium nitrate is prepared and maintained at a temperature above melting and below the lower of 500 degrees centigrade or the temperature of decomposition of the mixture. The enveloping metal container together with its included oxide crystal object is rotated within the heated KOH-KNO.sub.3 mixture, until the container is safely chemically machined away from the included oxide crystal object.

Inventors:
 [1];  [1]
  1. Livermore, CA
Issue Date:
Research Org.:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
OSTI Identifier:
867923
Patent Number(s):
5035769
Assignee:
United States of America as represented by United States (Washington, DC)
Patent Classifications (CPCs):
C - CHEMISTRY C23 - COATING METALLIC MATERIAL C23F - NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE
C - CHEMISTRY C30 - CRYSTAL GROWTH C30B - SINGLE-CRYSTAL-GROWTH
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
nondestructive; method; chemically; machining; crucibles; molds; enclosed; ingots; castings; inventive; described; rhenium; tungsten; alloy; 5b; 6b; included; comprised; oxide; crystals; including; yag; based; garnets; corundum; ceramic; oxides; mixture; potassium; hydroxide; 15; 90; weight; percent; nitrate; prepared; maintained; temperature; melting; below; 500; degrees; centigrade; decomposition; enveloping; metal; container; crystal; rotated; heated; koh-kno; safely; machined; nondestructive method; ceramic oxides; potassium nitrate; weight percent; ceramic oxide; potassium hydroxide; degrees centigrade; inventive method; metal container; tungsten alloy; oxide crystals; chemically machining; oxide crystal; /216/252/

Citation Formats

Stout, Norman D, and Newkirk, Herbert W. Nondestructive method for chemically machining crucibles or molds from their enclosed ingots and castings. United States: N. p., 1991. Web.
Stout, Norman D, & Newkirk, Herbert W. Nondestructive method for chemically machining crucibles or molds from their enclosed ingots and castings. United States.
Stout, Norman D, and Newkirk, Herbert W. Tue . "Nondestructive method for chemically machining crucibles or molds from their enclosed ingots and castings". United States. https://www.osti.gov/servlets/purl/867923.
@article{osti_867923,
title = {Nondestructive method for chemically machining crucibles or molds from their enclosed ingots and castings},
author = {Stout, Norman D and Newkirk, Herbert W},
abstractNote = {An inventive method is described for chemically machining rhenium, rhenium and tungsten alloy, and group 5b and 6b crucibles or molds from included ingots and castings comprised of oxide crystals including YAG and YAG based crystals, garnets, corundum crystals, and ceramic oxides. A mixture of potassium hydroxide and 15 to 90 weight percent of potassium nitrate is prepared and maintained at a temperature above melting and below the lower of 500 degrees centigrade or the temperature of decomposition of the mixture. The enveloping metal container together with its included oxide crystal object is rotated within the heated KOH-KNO.sub.3 mixture, until the container is safely chemically machined away from the included oxide crystal object.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1991},
month = {Tue Jan 01 00:00:00 EST 1991}
}