Sulfide stress cracking resistance of low-alloy nickel steels

Journal Article · Tue Apr 01 00:00:00 EST 1986 · Corrosion (Houston); (United States)

DOI:https://doi.org/10.5006/1.3586000· OSTI ID:5192712

Yoshino, Y; Minozaki, Y

The sulfide stress cracking (SSC) resistance of Ni-containing low-alloy steels was studied using laboratory and commercial heats over the range of 600 to 800 MPa yield strength (700 to 900 MPa tensile strength). The results were interpreted with regard to observations by metallurgical and electrochemical analyses. In steel containing 1% Cr and 0.5% Mo, the SSC resistance is not affected by up to 2% Ni. A commercial steel with 3.7% Ni-1.8% Cr-0.4% Mo exhibits the same K/sub ISSC/ and Ni-free steels. The cracking resistance begins to deteriorate when fresh martensite exceeds 5 vol%. The lattice diffusion of hydrogen is decreased by the additional Ni, whereas the subsurface hydrogen concentration remains constant in 5% NaCl solution and decreases in NACE TM-01-77 solution up to 5% Ni. Thus, nickel has no harmful effect in terms of hydrogen absorption and diffusion. However, nickel enhances the formation of surface trenches in acidified solutions. This is intensified in the anodically polarized slow extension rate test, which results in loss in elongation. Consequently, nickel per se has no effect on the propagation of SSC unless its addition results in the formation of fresh martensite. However, it may or may not enhance crack initiation, depending on a specific combination of solution and steel, by forming surface trenches that subsequently trigger hydrogen cracking from their bottom.

• Research Organization: Japan Steel Works, Ltd., Materials Research Lab., Chatsumachi 4, Muroran, Hokkaido 051
• OSTI ID: 5192712
• Journal Information: Corrosion (Houston); (United States), Vol. 42:4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
NICKEL-CHROMIUM STEELS
CORROSION RESISTANCE
CRACK PROPAGATION
STRESS CORROSION
SULFIDES
CORROSIVE EFFECTS
ABSORPTION
COMPARATIVE EVALUATIONS
DATA ANALYSIS
DIFFUSION
ELECTROCHEMISTRY
ELONGATION
HYDROGEN
HYDROGEN EMBRITTLEMENT
MARTENSITE
METALLURGICAL EFFECTS
METALLURGY
MOLYBDENUM ADDITIONS
PH VALUE
SODIUM CHLORIDES
SOLUTIONS
TENSILE PROPERTIES
VERY HIGH PRESSURE
YIELD STRENGTH
ALKALI METAL COMPOUNDS
ALLOYS
CARBON ADDITIONS
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
CHLORIDES
CHLORINE COMPOUNDS
CHROMIUM ALLOYS
CORROSION
DISPERSIONS
ELEMENTS
EMBRITTLEMENT
HALIDES
HALOGEN COMPOUNDS
IRON ALLOYS
IRON BASE ALLOYS
MECHANICAL PROPERTIES
MIXTURES
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NICKEL STEELS
NONMETALS
SODIUM COMPOUNDS
STEELS
SULFUR COMPOUNDS
360105* - Metals & Alloys- Corrosion & Erosion
360103 - Metals & Alloys- Mechanical Properties