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Comparative Evaluation of Impact Strength of Dissimilar Metal Weld between T91 and 304SS Prepared by SMAW and GTAW Techniques
Objectives: The main objective was to evaluate the better joint between dissimilar metals T91 (ferritic) and 304SS (austenitic) prepared by SMAW and GTAW in accordance to their impact strength. Methods/Statistical Analysis: Welding joints between T91 and 304SS were developed using two welding consumables 308L and 309L by SMAW and GTAW respectively. 4 plates of dimension 175mm x 100mm x 6mm were used for welding each of 304SS and T91. Total 9 specimens were prepared according to ASTM A370 standards (55mmX10mmX6mm) for Charpy impact testing, three each from weld bead, HAZ 304SS and HAZ T91 each from SMAW and GTAW welded plates. Findings: Impact strength testing was done with help of Charpy V-notch toughness machine. The standard specimens for Charpy impact testing was placed in the machine and values of impact strength were recorded one after another. As per results, the average impact strength of the weldment prepared by GTAW technique is marginally more as compared to SMAW technique for all sections. The impact strength of the GTAW specimen increases from 304SS HAZ to T91 HAZ passing through the weld metal. The best impact strength is obtained at T91 HAZ of GTAW joint which is 232.67 joules. This increased value of impact strength may be due to movement of carbon particles and formation of carbides and intermetallic. The enhancement in the impact strength is encountered due to increase in micro-hardness which is also published by various authors in the characterization of the weldments. The average impact strength of the weldment prepared by GTAW technique is more as compared to SMAW technique. The dissimilar metal joint prepared by GTAW technique is better joint in accordance to its impact strength. Improvement/Applications: Dissimilar metal joints between austenitic stainless steel and ferritic stainless steel are widely used in various fields like nuclear power plants, steam generators of power plants etc.
Dissimilar Metal Welding, Gas Tungsten Arc Welding (GTAW), Impact Toughness Comparison, Shielded Metal Arc Welding (SMAW).
- Kobelco. Welding today, why dissimilar welding is needed and how to select proper filler metals. The International Operational Department, Welding Company, Kobe Steel Ltd. 2002; 5:1–10.
- Parmar RS. Welding processes and technology. Khanna Publishers, New Delhi; 2012.
- The American Welding Society [Internet]. [cited 2016]. Available from: www.aws.com.
- B.I.S standard, No. 813-1986 (Revised), Indian Standards (BIS) on Welding [Internet]. [cited 1986]. Available from: https://law.resource.org/pub/in/bis/S10/is.813.1986.pdf.
- International Organization for Standards [Internet]. Available from: www.iso.com.
- Funderburk SR. Key concepts in welding engineering. Welding Innovation. 1997; 14(2):1–2.
- Kakani SL, Kakani A. Material Science. 3rd (Edn), New age international Publishers: India; 2016.
- Kou S. Welding Metallurgy. 2nd (Edn), John Wiley & Sons: US; 2003.
- Steel grades, properties and global standards [Internet]. [cited 2015 Nov 12]. Available from: http://steel-grades.com.hotsited.com.
- Mittal R, Sidhu BS. Micro structural and mechanical characterization of different zones of T91/T22 weldment. International Journal of Surface Engineering and Materials Technology. 2014 Jul–Dec; 4(5):45–9.
- Schaeffer AL. Selection of austenitic electrodes for welding dissimilar metals. Welding Journals. 1947; 26(10):601–20.
- ASTM E23. Standard test methods for notched bar impact testing of metallic materials [Internet]. [cited 2016 Apr 06]. Available from: http://mhriau.ac.ir/_DouranPortal/Documents/ASTM E23 (impact test)_20160406_233024.pdf.
- Kah DH, Dickinson DW. Weld ability of Ferritic Stainless Steels. Supplement to the Welding Journal. 1981 Aug:1–8.
- Jang C, Lee J, Kim JS, Jin JE. Mechanical property variation within Inconel 82/182 dissimilar metal weld between low alloy steel and 316 stainless steel. International Journal of Pressure Vessels and Piping. 2008 Sep; 85(9):635–46.
- Arivazhagan N, Singh S, Prakash S, Reddy GM. Investigation on AISI 304 austenitic stainless steel to AISI 4140 low alloy steels dissimilar joints by gas tungsten arc, electron beam and friction welding. Materials and Design. 2011 May; 32(5):3036–50.
- Karthik G, Karuppuswamy P, Amarnath V. Comparative evaluation of mechanical properties and micro structural characteristics of 304 stainless steel weldments in TIG and SMAW welding processed. International Journal of Current Engineering and Technology. 2014 Feb; S2:1–7.
- Timofeev BT, Karzov GP, Gorbakony AA, Nikolaev YK. Corrosion and mechanical strength of welded joints of downcomers for RBMK reactors. International Journal of Pressure Vessels and Piping. 1999 Apr; 76(5):299–307.
- Lundin CD, Lee CH, Menon R, Osorio V. Weld ability evaluations of modified 316 and 347 Austenitic stainless steels. Supplement to the Welding Journal. 1988 Feb:35–46.
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