Precipitation hardened nickel-base alloys for sour gas environments

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6952937

Igarashi, M; Mukai, S; Kudo, T; Okada, Y; Ikeda, A

SCC (Stress Corrosion Cracking) in sour gas environments of ..gamma..'(gamma prime: Ni/sub 3/(Ti and/or Al)) and ..gamma..''(gamma double prime: Ni/sub 3/Nb) precipitation hardened nickel-base alloys has been studied using the SSRT (Slow Strain Rate Tensile) test, anodic polarization measurement and transmission electron microscopy (TEM). The ..gamma..'-type alloy containing Ti was more susceptible to SCC in the SSRT tests up to 350/sup 0/F(450 K) than the ..gamma..''-type alloy containing Nb. The susceptibility to SCC was related to their deformation structures in terms of stress localization and sensitivity to pitting corrosion in H/sub 2/S solutions. TEM observation showed the ..gamma..'-type alloy deformed by the superlattice dislocations in coplanar structures. This mode of deformation induced the stress localization to some boundaries such as grain boundary and as a result the susceptibility to SCC of the ..gamma..'-type alloy was increased. On the other hand, the ..gamma..''-type alloy deformed by the massive dislocation not in coplanar structures so that it was less susceptible to SCC in terms of the stress localization. The anodic polarization measurement suggested the ..gamma..'-type alloy was more susceptible to pitting corrosion compared with the ..gamma..''-type alloy.

• OSTI ID: 6952937
• Report Number(s): CONF-870314-
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101 -- Metals & Alloys-- Preparation & Fabrication
360102 -- Metals & Alloys-- Structure & Phase Studies
360105* -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
ALUMINIUM ALLOYS
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
CORROSION
CORROSION RESISTANCE
CORROSIVE EFFECTS
CRACKS
ELECTRON MICROSCOPY
ENERGY SOURCES
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
HARDENING
MICROSCOPY
NATURAL GAS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ALLOYS
PITTING CORROSION
PRECIPITATION HARDENING
STRESS CORROSION
STRUCTURAL CHEMICAL ANALYSIS
TITANIUM ALLOYS
TRANSMISSION ELECTRON MICROSCOPY