Rapid Evaluation Method for the Degree of Sensitization of Stainless Steels by Using Random Potential Pulse.

In order to develop new design fatigue curves for carbon steels & low-alloy steels and austenitic stainless steels and a new design fatigue evaluation method that are rational and have clear design basis, Design Fatigue Curve (DFC) Phase 1 subcommittee and Phase 2 subcommittee were established in the Atomic Energy Research Committee in the Japan Welding Engineering Society (JWES). The study on design fatigue curves was actively performed in the subcommittees. In the subcommittees, domestic and foreign fatigue data of small test specimens in air were collected and a comprehensive fatigue database (≈6000 data) was constructed and the accurate best-fit curves of carbon steels & low-alloy steels and austenitic stainless steels were developed. Design factors were investigated. Also, a Japanese utility collaborative project performed large scale fatigue tests using austenitic stainless steel piping and low-alloy steel flat plates as well as fatigue tests using small specimens to obtain not only basic data but also fatigue data of mean stress effect, surface finish effect and size effect. Those test results were provided to the subcommittee and utilized the above studies. Based on the above studies, a new fatigue evaluation method has been developed.

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Interlaboratory Testing to Assess Repeatability and Reproducibility of the Double Loop Electrochemical Potentiokinetic Reactivation (DL-EPR) Tests for Type 304H Stainless Steels

CORROSION ◽

10.5006/3559 ◽

2020 ◽

Vol 76 (8) ◽

pp. 742-749

Author(s):

Raul B. Rebak ◽

Sheldon W. Dean

Keyword(s):

Stainless Steels ◽

Industrial Applications ◽

Double Loop ◽

Degree Of Sensitization ◽

Electrochemical Potentiokinetic Reactivation ◽

Degree Of Confidence ◽

Repeatability And Reproducibility ◽

Epr Test ◽

High Degree ◽

Interlaboratory Testing

The sensitization of stainless steels may decrease their corrosion resistance in industrial applications. Traditional immersion tests exist to determine the degree of sensitization (DOS) of the stainless steels. However, electrochemical methods may be preferred because they are less expensive and faster to perform. The fast and robust double loop electrochemical potentiokinetic reactivation (DL-EPR) test has been introduced to the corrosion community some decades ago but an interlaboratory testing study was necessary to assess the repeatability and reproducibility of the DOS results. This work reports on a recent study where 11 laboratories returned results that show a high degree of confidence in the data obtained by DL-EPR.

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Cementitious Activity Evaluation of Steel Slag by EDTA-NaOH Solution Extraction Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.893.389 ◽

2017 ◽

Vol 893 ◽

pp. 389-394

Author(s):

Zai Bo Li ◽

Tu Sheng He ◽

Xu Guang Zhao ◽

San Yin Zhao

Keyword(s):

Compressive Strength ◽

Extraction Method ◽

Evaluation Method ◽

Steel Slag ◽

Rapid Evaluation ◽

Mortar Strength ◽

Extraction Test ◽

Naoh Solution ◽

Cementitious Activity ◽

The Relationship

In order to establish a rapid evaluation method of steel slag cementitious activity, extraction test of steel slag in EDTA-NaOH solution have been investigated and the relationship between extraction characteristics and cementitious activity expressed as mortar strength has been analyzed. Results show that the linear relationship between the quantity extracted from steel slag and the mortar compressive strength is significant. According to the analysis results of mineral composition and microscopic morphologies, EDTA-NaOH solution can selectively extract the silicate and aluminate minerals of steel slag, which could be used as a rapid evaluation method of steel slag cementitious activity.

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A rapid evaluation method for degradation activation energy of n-GaAs ohmic contacts with and without TiN diffusion barrier layers

Proceedings of the 2001 8th International Symposium on the Physical and Failure Analysis of Integrated Circuits. IPFA 2001 (Cat. No.01TH8548) ◽

10.1109/ipfa.2001.941471 ◽

2002 ◽

Cited By ~ 1

Author(s):

Zhang Wan-rong ◽

Li Zhi-guo ◽

Mu Fu-chen ◽

Wang Li-xin ◽

Sun Ying-hua ◽

...

Keyword(s):

Activation Energy ◽

Diffusion Barrier ◽

Ohmic Contacts ◽

Evaluation Method ◽

Rapid Evaluation ◽

Barrier Layers ◽

Degradation Activation Energy ◽

Tin Diffusion Barrier

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Study on Incorporation of New Design Fatigue Curves and a New Environmental Fatigue Correction Factor for PWR Environment Into the JSME Environmental Fatigue Evaluation Method

Volume 1: Codes and Standards ◽

10.1115/pvp2020-21078 ◽

2020 ◽

Author(s):

Seiji Asada ◽

Shengde Zhang ◽

Masahiro Takanashi ◽

Yuichiro Nomura

Keyword(s):

Stainless Steel ◽

Base Metal ◽

Stainless Steels ◽

Evaluation Method ◽

Austenitic Stainless Steels ◽

Steel Base ◽

Improved Design ◽

Fatigue Evaluation ◽

Cast Stainless Steel ◽

Metal Weld

Abstract Improved design fatigue curves were developed in the Subcommittee on Design Fatigue Curve in the Atomic Energy Research Committee in the Japan Welding Engineering Society (JWES). Working Group on Design Fatigue Curves (WG DFC) in the JSME has studied the validity and the applicability of the improved design fatigue curves developed in the JWES to incorporate into the JSME Environmental Fatigue Evaluation Method. The authors propose a fatigue analysis method using the design fatigue curves developed in the JWES that are applied revised factors to optimize the environmental fatigue analysis. Also, the Japanese pressurized water reactor (PWR) utility group developed equations of environmental fatigue factors (Fen) for austenitic stainless steel base metal, weld metal and cast stainless steel in PWR environment. The WG DFC has investigated the Fen equations and concluded that the Fen equation of austenitic stainless steel base metal is the most conservative among the three equations and close to NUREG/CR-6909 Rev.1 [24]. The authors propose to use the Fen equation for base metal for austenitic stainless steels for all of the base metal, weld metal and cast stainless steel. In addition, the authors have confirmed that the employment of the proposed Fen equation to the proposed design fatigue curves of austenitic stainless steels accurately predicts the existing environmental fatigue test data of austenitic stainless steels, which were used in the development of the current Fen equation of austenitic stainless steels in PWR environments in the JSME Environmental Fatigue Evaluation Method. Therefore, the proposed Fen equation can be applied to environmental fatigue evaluation for austenitic stainless steels.

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