Property uniformity in tungsten heavy alloys

Conference · Sat Jan 01 04:00:00 EST 1983 · Prog. Powder Metall.; (United States)

OSTI ID:5496862

Eisenmann, M R; German, R M

The effect of variations in composition, sintering conditions, and post sintering heat-treatments were investigated for the W-Ni-Fe heavy alloys. Specific efforts are going into control and improvement of mechanical properties especially ductility and toughness. Liquid phase sintering of fine tungsten, nickel, and iron powders produces a high density, two-phase composite. The control of sintering time, temperature and atmosphere provides a basis for examining variations in density, grain size, and dissolution of tungsten into the matrix. Alloys containing 95-97.5 Wt.% W with Ni and Fe added in a 7:3 ratio, respectively, will determine the importance of W-W and W-matrix interfaces in improving toughness and ductility. Finally, post sintering heat-treatments will yield improvements in the mechanical properties of these heavy alloys by controlling the impurity distribution at the interfaces. A survey of the literature has attributed toughness variability to several factors including hydrogen embrittlement, interfacial impurity embrittlement, intermetallic formation, and phase morphology. Results of experiments designed to critically test these concepts will be given. Tentative findings indicate the nature of the interfaces in the W-Ni-Fe alloy controls toughness. This interfacial effect is adjustable though variations in microstructure, purity, and post sintering heat-treatments.

• Research Organization: Metal Powder Industries Federation, Princeton, NJ (USA); Rensselaer Polytechnic Institute, Troy, NY
• OSTI ID: 5496862
• Report Number(s): CONF-8205171-
• Conference Information: Journal Name: Prog. Powder Metall.; (United States) Journal Volume: 38
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
EMBRITTLEMENT
FABRICATION
HEAT TREATMENTS
IRON ALLOYS
MECHANICAL PROPERTIES
NICKEL ALLOYS
SINTERING
TUNGSTEN ALLOYS
TUNGSTEN BASE ALLOYS