• Journal of Welding and Joining
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• v.28 no.4
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• pp.49-54
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• 2010

Stainless steel sheets are widely used as the structural material for the railroad cars and the commercial vehicles. These kinds structures used stainless steel sheets are commonly fabricated by using the GMAW (gas metal arc welding). For fatigue design of GMA welded joints such as fillet and plug, ring type joint, it is important to obtain optimum design factor information on GMA welded joints. in this paper, analysis approach for fatigue test using design of experiment are evaluated optimum factor in GMA welded joint type and geometrical parameters of materials. Using these results, that factors applied to fundamental information for fatigue design.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.2
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• pp.38-43
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• 2015

Tungsten inert gas (TIG) welding is commonly used in industries that require airtightness, watertightness, oiltightness, and precision. It is a non-consumable welding method that is commonly used for the welding of non-ferrous metals, but it can be used to weld most metals. The methods of TIG welding can be divided into three types. The first, manual welding is done directly on the metal by a welder with a torch. The second, semi-automatic welding, gets help from a material supplying machine, but it is conducted by a welder. Lastly, automated welding is conducted fully by a machine during its process and operation. Depending on the selection of electrode, the amount of heat that is applied to the base material and the electrode rod changes and makes the shape of welded parts different. A direct-current positive electrode was used for this study. Through the change of shielding gas type on a structural steel (SS-400) that is commonly used in industry, the composition and shape changes in welded parts were detected after welding. The heat-affected area, hardness value, and tensile strength were also identified through hardness testing and tensile testing. In this study, it was found that the higher hardness value of the heat-affected is, the weaker the tensile strength becomes.

• Steel and Composite Structures
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• v.6 no.6
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• pp.531-555
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• 2006

H-shaped welded steel column members are fabricated by welding together pre-cut flanges and the web. Modern fabricators are increasingly using plasma-cutting technique instead of traditional flame cutting. Different fabrication techniques result in different degrees of geometric imperfections and residual stresses, which can have considerable influence on the strength of steel columns. This paper presents the experimental investigation based temperature profiles, geometric imperfections, and built-in residual stresses in plasma cut-welded H-shaped steel column members and in similar flame cut-welded H-shaped steel columns. Temperature measurements were taken during and immediately after the cutting operations and the welding operations. The geometric imperfections were established at closely spaced grid locations on the original plates, after cutting plates into plate strips, and after welding plate strips into columns. Geometric imperfections associated with plasma cut element and members were found to be less than those of the corresponding elements and members made by flame cutting. The "Method of Section" technique was used to establish the residual stresses in the plate, plate strip, and in the welded columns. Higher residual stress values were observed in flame cut-welded columns. Models for idealized residual stress distributions for plasma cut and flame cut welded sections have been proposed.

• Proceedings of the KWS Conference
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• 1998.10a
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• pp.234-235
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• 1998

• Proceedings of the KWS Conference
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• 2000.10a
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• pp.149-150
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• 2000

• Proceedings of the KWS Conference
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• 1996.05a
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• pp.122-122
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• 1996

• Proceedings of the KWS Conference
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• 1999.05a
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• pp.253-255
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• 1999

• Proceedings of the KWS Conference
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• 1996.10a
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• pp.79-81
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• 1996

• Proceedings of the KWS Conference
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• 1992.10a
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• pp.171-173
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• 1992

• Journal of Welding and Joining
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• v.27 no.6
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• pp.80-86
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• 2009

The Cu-bearing PFS-700 steel which has yield strength over 700 MPa was developed to replace the existing submarine structural material, HY-100. The PFS-700 steel has a combination of good mechanical properties and superior weldability. Becaus of that, it can be welded without pre-heating. The application of PFS-700 steel to submarine or battle ship will give a great reduction of cost by omitting pre-heating or lowering pre-heat temperature. To develop pre-heating free welding consumables that match and take advantage of PFS-700 steel, new welding consumables have been designed for the GMAW, SAW processes and explosion bulge test(EBT) was conducted to see the reliability of welded structure. All welds were made without pre-heating, and the inter-pass temperature was below $50^{\circ}C$ for SAW50 and $150^{\circ}C$ for GMAW and SAW150. All EBT specimens show over 14% thickness reduction without through-thickness crack or crack propagation to the hole-down area. Tensile properties for all welding conditions show higher(GMAW) or similar values(SAW50, SAW150) to the base metal. Charpy impact values for the weld metal also show 163.5J(GMAW), 95.4J(SAW50) and 69.0J(SAW150), which meet the goal(higher than 50J) of this project.