Effect of composition on corrosion resistance of high-alloy austenitic stainless steel weld metals
- British Aerospace, Bristol (United Kingdom)
- Welding Inst., Cambridge (United Kingdom)
The corrosion resistance of stainless steel weld metal in the ranges of 17 to 28% chromium (Cr), 6 to 60% nickel (Ni), 0 to 9% molybdenum (Mo), and 0.0 to 0.37% nitrogen (N) was examined. Critical pitting temperatures were determined in ferric chloride (FeCl[sub 3]). Passive film breakdown potentials were assessed from potentiodynamic scans in 3% sodium chloride (NaCl) at 50 C. Potentiodynamic and potentiostatic tests were carried out in 30% sulfuric acid (H[sub 2]SO[sub 4]) ar 25 C, which was representative of chloride-free acid media of low redox potential. Metallographic examination and microanalysis were conducted on the test welds. Because of segregation of alloying elements, weld metal pitting resistance always was lower than that of matching composition base steel. The difference increased with higher Cr, Mo, and N contents. Segregation also reduced resistance to general corrosion in H[sub 2]SO[sub 4], but the effect relative to the base steel was less marked than with chloride pitting. Segregation of Cr, Mo, and N in fully austenitic deposits decreased as the Ni[prime][sub eq-]Cr[prime][sub eq] ratio increased. Over the compositional range studied, weld metal pitting resistance was dependent mainly on Mo content and segregation. N had less effect than in wrought alloys. Both Mo and N enhanced weld metal corrosion resistance in H[sub 2]SO[sub 4].
- OSTI ID:
- 6239575
- Journal Information:
- Corrosion (Houston); (United States), Vol. 49:6; ISSN 0010-9312
- Country of Publication:
- United States
- Language:
- English
Similar Records
Applications of electrochemical methods for investigations of localized corrosion of nitrogen-molybdenium stainless steels
Pitting corrosion and crevice corrosion of an advanced chromium-based stainless steel
Related Subjects
CHROMIUM-NICKEL-MOLYBDENUM STEELS
CORROSION RESISTANCE
MOLYBDENUM
METALLURGICAL EFFECTS
WELDED JOINTS
IRON CHLORIDES
METALLOGRAPHY
MICROANALYSIS
NITROGEN
PITTING CORROSION
SEGREGATION
SODIUM CHLORIDES
SULFURIC ACID
ALKALI METAL COMPOUNDS
ALLOYS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CHROMIUM ALLOYS
CHROMIUM-NICKEL STEELS
CORROSION
ELEMENTS
HALIDES
HALOGEN COMPOUNDS
HIGH ALLOY STEELS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
IRON ALLOYS
IRON BASE ALLOYS
IRON COMPOUNDS
JOINTS
METALS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NONMETALS
SODIUM COMPOUNDS
STAINLESS STEELS
STEELS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
360105* - Metals & Alloys- Corrosion & Erosion