The Effect of Stand - Off Distance on the Mechanical Properties of TIG Butt Joints of 316 Stainless Steel

Abstract:

The objective of this study is to investigate and determine the effect of the stand-off distance (distance between the welded plates) on the mechanical properties of the Tungsten Inert Gas (TIG) welded joints. Butt TIG welding was performed for 316 stainless steel (SS) by using different pre welding stand-off distances with fixing the other parameters (thickness of welded plates, voltage, current, groove shape, and scanning speed). The influence of the stand-off distance parameter was examined by using tensile test, hardness test in the three different regions (base metal, heat effected zone, and molten zone), non-destructive testing (including visual inspection, liquid pentrant and X – ray) and microscopic examinations. Results show that the stand-off distance is one of the most important geometrical parameters of the Butt welded joints to end by good mechanical properties. It is found that the optimum stand-off distance was about 1 mm (shows the highest hardness results), but still there were some defects in some spots in the molten metal zone which caused a decrease in the hardness values in these locations. The 2 mm stand-off distance shows reasonable results, and the worst case was recorded for the 0 mm stand-off distance condition. Generally the hardness values of the heat affected zone in all conditions were the highest when compared to both metal welding zone and the base metal zone.

• Periodical: Key Engineering Materials (Volume 833)
• Pages: 59-65
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.833.59
• Online since: March 2020
• Authors: Hala M. Gnedi*, Khawla T. Snoussi, Abulmaali M.Y. Taher, Thoria G. Sharef, Yousef Arebi
• Keywords: 316 Stainless Steel, Butt Joints, Mechanical, Microstructure, NDT, Stand-Off Distance, TIG Welding

References

[1] 316/316L Stainless Steel, AK Steel Corporation, www.aksteel.com, (2007).

[2] Damian Kotecki and Frank Armao, "Stainless Steels Welding Guide. The Lincoln Electric Company, (2013).

[3] Liming Liu, Xujing Liu and Shunhua Liu, "Microstructure of laser-TIG hybrid welds of dissimilar Mg alloy and Al alloy with Ce as interlayer, Scripta Materialia,55, 2006, pp.383-386.

DOI: 10.1016/j.scriptamat.2006.04.025

[4] Ahmet Durgutlu, Experimental Investigation of the Effect of Hydrogen in Argon as a Shielding Gas on TIG Welding of Austenitic Stainless Steel,, Materials and Designs, 25, 2004, pp- 19–23.

DOI: 10.1016/j.matdes.2003.07.004

[5] Peng Liu, Yajiang Li, Haoran Geng , Juan Wanget, Microstructure Characteristics in TIG Welded Joint of Mg/Al Dissimilar Materials,, Materials Letters, 61, 2007, pp.1288-1291.

DOI: 10.1016/j.matlet.2006.07.010

[6] S. P. Gadewar, Peravali Swaminadhan,M. G. Harkare, S. H. Gawande, Experimental Investigations of Weld Characteristics for a Single Pass TIG Welding with SS304,, International Journal of Engineering Science and Technology, 2(8), 2010, pp.3676-3686.

[7] C. Balaji, S.V. Abinesh Kumar, S. Ashwin Kumar, R. Sathish, Evaluation of Mechanical Properties of SS 316 L Weldments using Tungsten Inert GasWelding,, International Journal of Engineering Science and Technology, 4, (2012).

[8] Cheng-HsienKuo, Kuang-Hung Tseng, Chang-Pin Chou, "Effect of Activated TIG Flux on Performance of DissimilarWelds between Mild Steel and Stainless Steel, Key Engineering Materials, 479, 2011, pp.74-80.

DOI: 10.4028/www.scientific.net/kem.479.74

[9] Paulo J. Modenesi, Eustaquio R. Apolina Ario, Iaci M. Pereira, TIG welding with Single-Component Fluxes,, Journal of Materials Processing Technology, 99, 2000, pp.260-265.

DOI: 10.1016/s0924-0136(99)00435-5

[10] Raghuvir Singh, N.M Suri, Jagjit Randhawa, Optimization of Process Parameters for TIG Welding of 304L Stainless Steel using Response Surface Methodology,. International Journal of Mechanical Science and Civil Engineering, 2 (2),June 2013 pp.36-40.

[11] S. Krishnanunni, Dr. Josephkunju Paul C, V NaraYanan Unni, Effect of Welding Conditions on Hardness of Commercially Pure Titanium,, Akgec Interna tional Journal of Technology, 3, (2), pp.19-24.

[12] R. Chhibber, N. Arora, S. R. Gupta, and B. K. Duta, Use of Bimetallic Welds in Nuclear Reactors: Associated Problems and Structural Integrity Assessment Issues,, Mechanical Engineering Science, 220, (2006).

DOI: 10.1243/09544062jmes135

[13] Dinesh Kumar.R, Elangovan.S2, Siva Shanmuam. N, Optimizations of Pulsed TIG Welding Process in Butt Joining of 304L Austenetic Stainless Steel Sheets", International Journal of Research in Engineering and Technology, 3 (1), (2014).

DOI: 10.15623/ijret.2014.0323047