CVD parameter study using strategy of experimentation

Technical Report · Sun Jul 01 04:00:00 EDT 1984

OSTI ID:6686988

Williams, R E

An experimental design strategy was used to determine the operating characteristics of an apparatus for forming tungsten-rhenium (W-Re) alloys by chemical vapor deposition. The metal deposits were made at 650/sup 0/C by the hydrogen reduction of a 10 percent rhenium hexafluoride and 90 percent gas mixture at 0.66 to 4.00 kPa (5 to 30 torr). Hydrogen flow rates ranged from 550 to 2770 ..mu..mol/s and mixed metal fluoride flows ranged from 41 to 130 ..mu..mol/s. An operating point was sought that would produce a high strength alloy, so the deposition results were fit by least squares regression to second order response equations. Seven properties were measured: deposition rate, average composition, maximum composition, minimum composition, sample standard deviation of the composition, microhardness as a measure of the amount of A15 phase, and as-deposited surface quality. A set of operating parameters was determined that was predicted to yield a 23 w/o Re alloy with an 1100 DPH (diamond pyramid hardness) microhardness.

• Research Organization: Bendix Corp., Kansas City, MO (USA)
• DOE Contract Number: AC04-76DP00613
• OSTI ID: 6686988
• Report Number(s): BDX-613-3090; ON: DE84015900
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
ALLOYS
CHEMICAL COATING
CHEMICAL REACTIONS
CHEMICAL VAPOR DEPOSITION
DEPOSITION
ELEMENTS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HYDROGEN
NONMETALS
PARAMETRIC ANALYSIS
REDUCTION
RHENIUM ALLOYS
RHENIUM COMPOUNDS
RHENIUM FLUORIDES
RHENIUM HALIDES
SURFACE COATING
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN ALLOYS