Microstructure limitations of high tungsten content heavy alloys

Journal Article · Thu Aug 01 04:00:00 EDT 1985 · J. Met.; (United States)

DOI:https://doi.org/10.1007/BF03257677· OSTI ID:6123501

German, R M; Bourguignon, L L; Rabin, B H

Heavy alloys are tungsten-based materials which rely on nickel and iron additions to form a liquid phase during sintering. The resulting material is a two phase composite consisting of tungsten grains in an alloy matrix. An example microstructure for an alloy with 95 wt.% tungsten is shown. The grains are nearly pure tungsten, while the matrix is an alloy of approximately 20 wt.% W, 55 wt.% Ni and 25 wt.% Fe. A nickel to iron ratio of 7:3 is optimal in these alloys since this composition avoids the formation of intermetallic phases. In forming the alloy, mixed powders of micrometer sizes are compacted and sintered at temperatures over the eutectic temperature of 1435/sup 0/C. The resulting alloys have high theoretical densities because of the large tungsten content; additionally, the sintered materials have high ductilities and strengths because of the ductile matrix.

• Research Organization: Rensselaer Polytech Institute, Materials Engineering Department
• OSTI ID: 6123501
• Journal Information: J. Met.; (United States), Journal Name: J. Met.; (United States) Vol. 37:8; ISSN JOMTA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
360102 -- Metals & Alloys-- Structure & Phase Studies
360103 -- Metals & Alloys-- Mechanical Properties
ALLOYS
CHEMICAL COMPOSITION
CRYSTAL STRUCTURE
FABRICATION
FRACTURE PROPERTIES
IMPURITIES
IRON ALLOYS
MATERIALS
MATRIX MATERIALS
MECHANICAL PROPERTIES
METALLURGICAL EFFECTS
MICROSTRUCTURE
NICKEL ALLOYS
QUANTITY RATIO
SINTERING
TEMPERATURE EFFECTS
TENSILE PROPERTIES
TUNGSTEN ALLOYS
TUNGSTEN BASE ALLOYS
VERY HIGH TEMPERATURE