Refine your search
Collections
Co-Authors
Journals
Year
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Nanavati, P. K.
- An Experimental Comparative Review of Ferrite Measurement Techniques Used in Duplex Stainless Steel (UNS S32205) Welds
Abstract Views :324 |
PDF Views:15
Authors
Affiliations
1 Metallurgy Department, Government Engineering College, Sec-28, Gandhinagar, Gujarat, IN
2 Metallurgical and Materials Engineering Department, The M.S.University of Baroda, Vadodara, Gujarat, IN
1 Metallurgy Department, Government Engineering College, Sec-28, Gandhinagar, Gujarat, IN
2 Metallurgical and Materials Engineering Department, The M.S.University of Baroda, Vadodara, Gujarat, IN
Source
Indian Welding Journal, Vol 51, No 2 (2018), Pagination: 75-83Abstract
Duplex stainless steels (DSS) have proven to be very promising engineering materials as substitutes to conventional austenitic stainless steels for structure of off-shore platforms, parts and equipment in petrochemicals and refinery industries, predominantly for sour service applications where corrosion resistance including stress corrosion cracking (SCC) resistance is required in aggressive chloride and/or sulphide environments. Resistance to SCC in chloride containing environment depends on the available ferrite content in the carefully welded duplex (ferritic-austenitic) stainless steel structure. There is, of course, a degree of variation in weld metal ferrite content and in reproducibility of measurement which deserve a review and comparative study on different weld metal ferrite measurement techniques being widely used. So, present work has been carried out by collaborating with a reputed filler metal manufacturer who deliberately produced special batches of standard DSS compositions matching SMAW electrodes with nickel varied content in the range of 9-9.5 %, 9.5-10.5, 10.5-11.5 and 11.5 to 12.5 % to obtain weld deposits in varied ferrite content range15% to 40%, or 20 FN to 50 FN to be experimentally investigated by (1) Feritscope® instrument method, (2) ASTM E 562-11 volume fraction measurement by systematic manual point count method and (3) theoretically by WRC-1992 Diagram. The purpose of this paper is to give a comparative overview of above methods. According to the findings of the study, readings on the top surface of weld metal were consistent with those on the cross section, this indicates proper guidelines can be given for selecting location of testing Feritscope® instrument measurement. FN estimates in predictive methods like image analysis/manual point count methods depends on proper placement of the points on ferrite grains morphology, fineness, discreteness and its irregularity.Keywords
Duplex Stainless Steels, % Ferrite, Ferrite Number, Feritscope®, Volume Fraction Measurements, WRC-1992 Diagram, Weld Metal Dilution, Grain Morphology.
References
- API Technical report 938-C (2015); Use of duplex stainless steels in the oil refining industry, 9th Edition, pp. 2-7.
- Messer B, Oprea V and Wright A (2007); Duplex stainless steel welding: best practices, Stainl. Steel World, (December), pp. 53–63.
- IMOA (2001); Practical Guidelines for the Fabrication of Duplex Stainless Steels, Revised Edition, International Molybdenum Association, USA. pp. 14-17.
- Arnaldo FJ, et al. (2011); Comparative study of ferrite quantification methods applied to duplex stainless steel, Proceedings of the 7th European Stainless Steel Conference- Science and Market; Milan, Italy.
- Tavares SSM, Pardal JM, Abreu HFG, Nunes CS, Silva MR (2012); Tensile properties of duplex UNS S32205 and lean duplex UNS S32304 steels and the influence of short duration 475 °C aging, Materials Research, 15(6), pp. 859-864.
- Arnaldo FJ, Otubo J, Magnabosco R (2016); Ferrite Quantification Methodologies for Duplex Stainless Steel, J. of Aerosp Technol. and Manag., 8(3).
- Bermejo MAV (2012); Predictive and measurement methods for delta ferrite determination in stainless steels, Welding Journal, 91, pp.113s-121s.
- ASTM A800/A800M-14, Standard Practice for Steel Casting, Austenitic Alloy, Estimating Ferrite Content Thereof.
- ISO 8249:2000, Welding-Determination of Ferrite Number (FN) in austenitic and duplex ferritic-austenitic Cr-Ni stainless steel weld metals.
- ASTM E562 -2011, Standard Practice for Determining Volume Fraction by Systematic Manual Point Count.
- Kotecki DJ and Siewert TA (1992); WRC-1992 constitution diagram for stainless steel weld metals : a modification of the WRC-1988 diagram, Welding Journal, 71(5), pp. 171-s–178-s.
- Lippod JC, Kotecki D (2005); Welding Metallurgy & Weldability of Stainless Steels, John Wiley and Sons, pp. 234-262.
- Kotecki D (1986); Ferrite control in duplex stainless steel weld metal, Weld. J., 65(10), pp. 273-s-278-s.
- Kotecki DJ (1997); Ferrite determination in stainless steel welds-advances since 1974, Welding Journal, 76(1), pp.24-s to 37-s.
- Kotecki DJ and Siewert TA (1992); WRC-1992 constitution diagram for stainless steel weld metals: a modification of the WRC-1988 diagram, Welding Journal, 71(5), pp. 171-s to178-s.