Surface and grain boundary segregation, stress corrosion cracking, and corrosion fatigue of Inconel 600

Technical Report · Fri Mar 01 04:00:00 EST 1985

OSTI ID:5701885

Smialowska, S; Cragnolino, G; Macdonald, D D

The stress corrosion cracking of Inconel 600 in environments related to nuclear power systems was studied in relation to the role of segregation in the alloy. Auger electron spectroscopy was used to evaluate the surface segregation of different impurities in Inconel 600 as a function of heat-to-heat variation and heat treatment. The degree of segregation of various elements (S, P, N, Ti, Si, and C) on the fracture surface of nickel was also evaluated as a function of the heat treatment employed, temperature, and cooling rate. The effects of alloying elements, added to nickel with the aim of reducing sulfur segregation to grain boundaries, was also studied. The susceptibility of nickel to intergranular corrosion in acidic and alkaline solutions at different potentials was measured as a function of sulfur segregation to the grain boundaries. The effect of heat treatment and applied potential on the caustic stress corrosion cracking susceptibiliy of Inconel 600 was studied in concentrated NaOH solutions at 140/sup 0/C using the slow strain rate technique. The corrosion fatigue resistance of Inconel Alloy 600 in concentrated NaOH solutions at 140/sup 0/C was evaluated as a function of heat treatment conditions using smooth bar specimens. The results have shown that the stress corrosion behavior of Inconel 600 in caustic solutions differs greatly from that in acidic and nearly neutral environments. Furthermore, sensitization by heat treatment was found to be beneficial under caustic corrosion conditions but detrimental in acidic environments.

• Research Organization: Ohio State Univ., Columbus (USA). Dept. of Metallurgical Engineering
• OSTI ID: 5701885
• Report Number(s): EPRI-NP-3949M; ON: TI85920590
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALKALI METAL COMPOUNDS
ALLOYS
AQUEOUS SOLUTIONS
AUGER ELECTRON SPECTROSCOPY
CHEMICAL REACTIONS
CHROMIUM ALLOYS
CORROSION
DISPERSIONS
ELECTRON SPECTROSCOPY
HEAT TREATMENTS
HIGH TEMPERATURE
HYDROGEN COMPOUNDS
HYDROXIDES
IMPURITIES
INCONEL 600
INCONEL ALLOYS
IRON ALLOYS
MIXTURES
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ALLOYS
OXYGEN COMPOUNDS
SEGREGATION
SODIUM COMPOUNDS
SODIUM HYDROXIDES
SOLUTIONS
SPECTROSCOPY
STRESS CORROSION