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

Patent Application · Wed Oct 04 00:00:00 EDT 1989

OSTI ID:5764284

Stout, N D; Newkirk, H W

An inventive method is described for chemically machining rhenium, rhenium and tungsten alloy, and group 5b and 6b metal 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. 1 fig.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (USA)
• DOE Contract Number: W-7405-ENG-48
• Assignee: Dept. of Energy
• Patent Number(s): PATENTS-US-A7417146
• Application Number: ON: DE91011610; PPN: US 7-417146
• OSTI ID: 5764284
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINATES
MOLDING
ALUMINIUM OXIDES
ALUMINIUM SILICATES
CALCIUM SILICATES
CHROMIUM
CHEMICAL MACHINING
CHROMIUM SILICATES
IRON SILICATES
MAGNESIUM SILICATES
MANGANESE SILICATES
MOLYBDENUM
NIOBIUM
RHENIUM
RHENIUM ALLOYS
TANTALUM
TUNGSTEN
TUNGSTEN ALLOYS
VANADIUM
YTTRIUM COMPOUNDS
PATENTS
POTASSIUM HYDROXIDES
POTASSIUM NITRATES
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
ALUMINIUM COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
CHROMIUM COMPOUNDS
DOCUMENT TYPES
ELEMENTS
FABRICATION
HYDROGEN COMPOUNDS
HYDROXIDES
IRON COMPOUNDS
MACHINING
MAGNESIUM COMPOUNDS
MANGANESE COMPOUNDS
METALS
NITRATES
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POTASSIUM COMPOUNDS
SILICATES
SILICON COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication