Ferrite Measurement and Control in Cast Duplex Stainless Steels

Aubrey, LS; Wieser, PF; Pollard, W.A.; Schoefer, E. A.

doi:10.1520/stp28440s

Cited by 11 publications

(6 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ferrite content was measured with a ferrite scope and calculated from the chemical composition in terms of Hull's equivalent factors. 16 Fabrication and procurement history of the weldments is as follows:…”

Section: Materials Characterizationmentioning

confidence: 99%

Effects of thermal aging on fracture toughness and charpy-impact strength of stainless steel pipe welds.

Gavenda¹,

Michaud²,

Galvin³

et al. 1996

View full text Add to dashboard Cite

The degradation of fracture toughness, tensile, and Charpy-impact properties of Type 308 stainless steel (SS) pipe welds due to thermal aging has been characterized at room temperature and 290°C. Thermal aging of SS welds results in moderate decreases in Charpy-impact strength and fracture toughness. For the various welds in this study, upper-shelf energy decreased by 50-80 J/cm 2 . The decrease in fracture toughness J-R curve or J IC is relatively small. Thermal aging had little or no effect on the tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second-phase particles. Failure occurs by the formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on the fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical-property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds.

show abstract

Section: Materials Characterizationmentioning

confidence: 99%

Effects of thermal aging on fracture toughness and charpy-impact strength of stainless steel pipe welds.

Gavenda¹,

Michaud²,

Galvin³

et al. 1996

View full text Add to dashboard Cite

show abstract

“…The chemical composition, hardness, and ferrite content and distribution of the cast materials are given in Table 1. For each material, the ferrite content calculated from the composition with Hull's equivalent factor 24 are also listed in the table.…”

Section: 2 Materials Characterizationmentioning

confidence: 99%

Tensile-property characterization of thermally aged cast stainless steels.

Michaud¹,

Toben²,

Soppet³

et al. 1994

View full text Add to dashboard Cite

The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components. Executive SummaryCast duplex stainless steels used in light water reactor (LWR) systems for primary pressure-boundary components are susceptible to thermal embrittlement at reactor operating temperatures. Thermal aging of cast stainless steels at these temperatures causes an increase in hardness and tensile strength and a decrease in ductility, impact strength, and fracture toughness of the material and the Charpy transition curve shifts to higher temperatures. Investigations at Argonne National Laboratory have shown that thermal embrittlement of cast stainless steel components may occur within the reactor design lifetime of 40 yr. Various grades and heats of cast stainless steel exhibit varying degrees of thermal embrittlement. In general, the low-C CF-3 steels are the most resistant t o thermal embrittlement, and the Mobearing, high-C CF-8M steels are the least resistant. An assessment of mechanical-property degradation due to thermal embrittlement is therefore required to evaluate the performance of cast stainless steel components during prolonged exposure to service temperatures, because rupture of the primary pressure boundary could lead to a loss-of-coolant accident and possible exposure of the public to radiation.This report presents tensile-property data on several heats of cast stainless steels aged up to 58,000 h at temperatures between 290 and 450°C (554 and 752°F). The tensile data are analyzed to establish the effects of thermal aging on tensile strength and engineering stress-strain behavior (represented by the Ramberg-Osgood equation) of cast stainless steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stress, and in the engineering stress-vs.-strain curve of cast stainless steel components due to thermal aging during service in LWRs. The tensile properties of aged cast stainless steel are estimated from information that is readily available from certified material test records for the component, i.e., chemical composition and the initial tensile strength of the unaged material. The correlations described in this report may be used ...

show abstract

“…The process of electrochemical corrosion and SCC of 321SS is different from that of other stainless steels because Ti can induce the generation of delta phase [38] . However, the impacts of δ phase on the behavior of electrochemical corrosion and SCC is not completely unified.…”

Section: Introductionmentioning

confidence: 98%

Effect of low dose irradiation of heavy ion on electrochemical corrosion and IASCC behavior of austenitic steel

Gao,

Cao,

et al. 2023

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

The impacts of low dose irradiation on the behavior of electrochemical corrosion and irradiation assisted stress corrosion cracking for 321 stainless steel were studied using Fe2+ ion irradiation to simulate neutron radiation damage in primary circuit environment of pressurized water reactor. Low dose irradiation can improve the pitting resistance and reduce the cracking tendency of the alloy in B-Li solution to a certain extent, which was related to the δ phase content on the near-surface of the sample: The higher δ phase content on the near-surface of the 2 dpa irradiated sample was observed by grazing incident X-ray diffraction. In addition, the pits was significantly increased near micro-cracks for the unirradiated sample, indicating that the existence of pits induced the initiation of cracks. The research results provided an important reference for the failure mechanism of irradiation assisted stress corrosion cracking of core components.

show abstract

Ferrite Measurement and Control in Cast Duplex Stainless Steels

Cited by 11 publications

References 4 publications

Effects of thermal aging on fracture toughness and charpy-impact strength of stainless steel pipe welds.

Effects of thermal aging on fracture toughness and charpy-impact strength of stainless steel pipe welds.

Tensile-property characterization of thermally aged cast stainless steels.

Effect of low dose irradiation of heavy ion on electrochemical corrosion and IASCC behavior of austenitic steel

Contact Info

Product

Resources

About