A Study of Parameters Affecting to Mechanical Property of Dissimilar Welding between Stainless Steel (AISI 304) and Low Carbon Steel

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1 A Study of Parameters Affecting to Mechanical Property of Dissimilar Welding between Stainless Steel (AISI 304) and Low Carbon Steel S. KAEWKUEKOOL 1, B. AMORNSIN 2 1 Department of Production Technology Education King Mongkut's University of Technology Thonburi 126 Pracha-utid Rd. Bangmod Toong-kru, Bangkok THAILAND 2 Sakonnakorn Technical College 219 Moo 11 Nitayo Rd. Maung District, Sakonnakhon THAILAND Abstract: The purpose of this paper was to study parameters affecting to mechanical property of dissimilar welding between stainless steel (AISI 304) and low carbon steel using gas metal arc welding technique. Factors using in this study were filler metal, speed, and current and each factor was set at three levels in the experiment. The experiment was run using factorial design to find out the relationship of factors that might be affected to mechanical property on tensile strength and elongation. After running the experiment, data was collected using the tensile testing machine. The results showed that interaction affects of filler metal, speed, and current factors were showed significantly different on the ultimate tensile strength and elongation at the level of.01. This could be concluded that changing of level of factors would be affected to the mechanical property of dissimilar welding between stainless steel (AISI 304) and low carbon steel. Key-Words: Mechanical Property / Dissimilar Welding / Tensile Strength 1 Introduction Stainless steel is the metal that has higher corrosion resistance with major composition of ferrite, chromium, and nickel has carbon composition less than 12%. This kind of material is easy to form in different and well known use in several types of industries such electrical, chemical oil, and transportation industries. Beside, low carbon steel is well known used for several industries as well. However, event though both materials are having different chemical composition, they have been in the same industry. Based on different chemical composition, it is difficult to melt both materials to use for some reasons without affecting to mechanical proper changing. T. W. NELSON, J.C. LIPPOLD and M. J.MILLS [1] was studied for dissimilar welding for different kinds of stainless with 70Ni-30Cu (AWS A5.14 ERNiCu-7) filler type. The result showed that there was affected to micro structure. Moreover, E.J. BARNHOUS and J.C. LIPPOLD [2] was studied in changing of micro structure and corrosion resistance of dissimilar welding between duplex stainless steel and plain carbon structural steel with Filler Metal ER 2209 and Ni-Based Alloy 625 using Gas Tungsten Arc Welding (GTAW). The result showed that there were affected to mechanical property and micro structure around heat affected zone (HAZ). Beside previous studies, some problems occurred when studying in dissimilar welding were hot cracking, Intergranular corrosion, Influence of impurity elements, Weld decay, Stress Corrosion Cracking, and so on [3]. Based on previous study on results and problems, the objective of this study was to find out the factors that affecting to mechanical property of ultimate tensile strength and elongation for dissimilar welding between stainless steel (AISI 304) and low carbon steel. 2 Methodology 2.1 Independent Factors There were three independent factors using in this study and each factor was run in three different levels as shown in the following: ISSN: ISBN:

2 - Welding wires were 304L, 308L, and 316L - s of welding were, 350, and 450 mm/min - s were 120, 140, and 160 Amp. 2.2 Equipments, materials, and tools The experiment was run by using automatic welding machine brand name CIGWELD and fixture using to grab the materials showed in Figure 1, and Figure Pilot Study Pilot study was been applied to find out the appropriate factors and levels to indicate that factors selected could be used for this study. 2.4 Experimental Design The experiment was factorial design of three different factors and each factor was run randomly at three different levels. Each combination of factor was run two replicate, which was total of 54 replicates as shown in Table 1. Table 1 Experiment Design Filler metal mm/min 350 mm/min 450 mm/min Amp. Amp. Amp. Fig. 1 Automatic welding machine brand name CIGWELD 304L 308L 316L Procedure All replicates shown in the Table 1 were randomly selected to run for experiment using standard position 1G. Figure 3 shows the work of dissimilar welding of stainless steel AISI 304 and low carbon steel. Fig. 2 Fixture using to grab the materials Materials used in the experiment were stainless steel AISI 304 and low carbon steel having dimension of 60 x 150 x 5 mm. Fig. 3 showing of GMAW method welding ISSN: ISBN:

3 2.6 Data Collection Data was collected on ultimate tensile strength and elongation applied ASME standard section IX [4]. 280 of Tensile strength At Filler type = 304L 3 Results 3.1 Ultimate Tensile Strength The results of ultimate tensile strength for dissimilar welding between stainless steel (AISI 304) and low carbon steel were showed significantly different for interaction affect of filler metal, speed, and current at the level of.01 as shown in Table 2. The interaction affect was shown in different ultimate tensile strength when each factor was run at different level as shown in Figure Fig. 4 Estimated marginal means of tensile strength for filler type 304L Table 2 ANOVA result of ultimate tensile strength Treatment SS d f MS F Sig. Filler Filler * Figure 5 was shown the estimated marginal means of tensile strength for filler metal type 308L. As the results, using the speed of welding at mm/min and the current at 120 amps would be given the highest tensile strength approximately of 270 N/mm of Tensile strength At Filler type = 308L Filler * * Filler * * Error Total Figure 4 was shown the estimated marginal means of tensile strength for filler metal type 304L. As the results, using the speed of welding at mm/min and the current at 160 amps would be given the highest tensile strength of 275 N/mm 2 Fig. 5 Estimated marginal means of tensile strength for filler type 308L Finally, figure 6 was shown the estimated marginal means of tensile strength for filler metal type 316L. The result was showed the same of using filler metal type 304L. Using the speed of welding at mm/min and the current at 160 amps would be given the highest tensile strength of 262 N/mm 2 ISSN: ISBN:

4 264 of Tensile strength At Filler type = 316L 13.5 of Elongation At Filler type = 304L Fig. 6 Estimated marginal means of tensile strength for filler type 316L Fig. 7 Estimated marginal means of elongation for filler type 304L 3.2 Elongation The results of elongation for dissimilar welding between stainless steel (AISI 304) and low carbon steel were showed significantly different for interaction affect of filler metal, speed, and current at the level of.01 as shown in Table 3. The interaction affect was shown in different elongation when each factor was run at different level as shown in Figure 7-9. Table 3 ANOVA result of elongation Treatment SS d f MS F Sig. Filler Filler * Filler * * Similarly, the estimated marginal means of elongation for filler metal type 308L was showed the same of filler type 304L as shown in Figure 8. As the results, using the speed of welding at mm/min and the current at 120 amps would be given the highest elongation of 12.3 mm of Elongation At Filler type = 308L 9.0 Fig. 8 Estimated marginal means of elongation for filler type 308L Filler * * Error E-02 Total Figure 7 was shown the estimated marginal means of elongation for filler metal type 304L. As the results, using the speed of welding at mm/min and the current at 120 amps would be given the highest elongation of 13.2 mm. Finally, figure 9 was shown the estimated marginal means of elongation for filler metal type 316L. The result was showed that using speed of welding at mm/min and the current at 140 amps would be given the highest elongation of 14.3 mm. ISSN: ISBN:

5 14.5 of Elongation At Filler type = 316L [4] Donal T Hawkins and Ralph Hultgren, 1995, Metal Hand book. Volume 8, Metallography Structures and Phase Diagram, 8 th Edition, American Society for Metals (ASM), Metal Parks Ohio, USA. pp Fig. 9 Estimated marginal means of elongation for filler type 316L 4. Discussion and Conclusion As the results, they were shown that interaction factor of filler metal, speed, and current have been affected to the mechanical property of dissimilar welding between stainless steel (AISI 304) and low carbon steel. The result that was provided the highest ultimate tensile strength significantly different at the level of.01 was the interaction of filler type 304L, speed of mm/min and current at 160 amps and provide the tensile strength of 275 N/mm 2. Moreover, the elongation result was showed significantly different at the level of.01 that interaction affect of filler type 316L, speed of mm/min and current at 140 amps were provided the highest elongation of 14.3 mm. 5. Refference [1] T. W. NELSON, J. C. LIPPOLD AND M. J. MILLS Ohio State University, Nature and Evolution of the Fusion Boundary in Ferritic- Austenitic Dissimilar Metal Welds -Part 2: On- Cooling Transformations WELDING JOURNAL, October, 2000 Sponsored by the American Welding Society and the Welding Research Council. pp [2] E.J. Barnhouse and J.C. Lippold, 1998, Microstructure/Property Relationships in Dissimilar Welds between Duplex Stainless Steel and Carbon Steel: pp [3] BROOKS, J. A. and LAMBERT, Jr. F. j. 2003, The effect of phosphorus sulfur and ferrite content on weld cracking of type 309 stainless steel, Welding Journal (May 2003): pp ISSN: ISBN: