PSI- Issue 9

Tareq Rahman Mahmood et al. / Procedia Structural Integrity 9 (2018) 71–85 Tareq RahmanMahmood, et al. / Structural Integrity Procedia 00 (2018) 000–000

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2.1. Welding process parameters It was observed that the welding times less than 12 cycles producing an incomplete penetration. On the other hand, welding times greater than 43 cycles will result weld splash, spatter, and excessive electrode penetration. Also, the welding currents less than 5 kA resulted in imperfect penetration and lack of fusion. The currents more than 8.5 kA producing weld splash and spatter (Al-Mukhtar 2016, 2015; Daws et al. 2003). In this study, three parameters have been optimized; current-I, welding time-T, and electrode force-F. The holding time was fixed. Design Expert Software verified 27 different welding trials run. Each trial run has different value of process parameters. The 27 trials run will be welded. Thereafter, the tensile test performed for each run, see table 3.

Table 3. Run sheet table from design expert program for low carbon steel with 0.9 mm thickness. Run F (N) I (Amp.) T (cycle) Tensile force, T.F (KN) 1 1900 5850 40 3.155 2 2150 5550 40 1.99 3 2150 5850 15 2.5 4 2640 8250 40 6.63 5 2150 7050 26 5.41 6 1900 5550 26 2.57 7 2640 7050 40 5.315 8 1900 7800 30 6.71 9 1900 5550 15 3 10 2150 7950 40 6.695 11 2150 8250 20 6.86 12 2150 5550 26 2.82 13 2640 8250 15 6.51 14 2640 8250 26 6.52 15 1900 7500 15 6.34 16 2150 7050 15 5.68 17 2640 7050 26 5.11 18 1900 7050 40 5.93 19 2640 5550 15 1.2 20 2150 8250 15 6.722 21 1900 8250 26 6.166 22 2640 5550 26 2.77 23 2640 5550 40 2.85 24 2150 7350 40 6.1 25 1900 7050 26 5.35 26 1900 7050 15 5.95 27 2640 7050 15 5.125