Stress corrosion cracking behavior of tungsten heavy alloys

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5054835

Chung, J G

Stress-corrosion cracking behavior of 90 W-Ni-Fe (W-10) and 97 W-Ni-Fe-Cu-Co (W-3) alloys was studied in solutions of NaCl, NACE, and 10% H/sub 2/SO/sub 4/. The influences of electrochemical polarization, and hydrogen catalyst, and heat treatment on K/sub ISCC/, static load crack growth rate, and fracture morphology were studied. The W-10 alloy exhibited SCC susceptibility in NaCl solution. Electrochemical polarization, addition of a hydrogen catalyst (As) to the NaCl solution, and heat treatment in hydrogen increased SCC susceptibility. SCC susceptibility was also observed in the sulfide cracking solution and when cathodically charged in 10% H/sub 2/SO/sub 4/ with a hydrogen catalyst (As). At the corrosion potential and anodic potentials in NaCl solution, SCC propagated by separation of tungsten-tungsten and tungsten-matrix interfaces with ductile rupture of the matrix. In other cases, cracks propagated by separation of tungsten-matrix and tungsten-tungsten interfaces with some cleavage of tungsten grains. The W-3 alloy did not exhibit SCC susceptibility in NaCl solution, under any conditions. SCC did occur in the sulfide cracking solution and when cathodically charged in 10% H/sub 2/SO/sub 4/ with a hydrogen catalyst (As), however, it was much more resistant than the W-10 alloy. Fracture occurred primarily by dimple formation in the matrix and cleavage of tungsten grains.

• Research Organization: Rensselaer Polytechnic Inst., Troy, NY (USA)
• OSTI ID: 5054835
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
360105* -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
CHEMICAL REACTIONS
CHEMISTRY
CORROSION
CRACK PROPAGATION
DATA
ELECTROCHEMISTRY
EXPERIMENTAL DATA
HEAT TREATMENTS
INFORMATION
NUMERICAL DATA
STRESS CORROSION
TUNGSTEN ALLOYS
TUNGSTEN BASE ALLOYS