• Journal of Welding and Joining
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• v.23 no.5
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• pp.61-68
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• 2005

Dissimilar joining of Al 6013-T4 alloys and austenite stainless steel was carried out using friction stir welding technique. Microstructures near the weld zone and mechanical properties of the joint have been investigated. Microstructures in the stainless steel side were composed of the heat affected zone and the plastically deformed zone, while those in the Al alloy side were composed of the recrystallized zone including stainless steel particles, the thermo-mechanically affected zone and the heat affected zone. TEM micrographs revealed that the interface region was composed of the mixed layers of elongated stainless steel and ultra-fine grained Al alloy with lamella structure and intermetallic compound layer. Thickness of the intermetallic layer was approximately 300nm and was identified as the A14Fe with hexagonal close packed structure. Mechanical properties, such as tensile and fatigue strengths were lower than those of 6013 Al alloy base metal, because tool inserting location was deviated to Al alloy from the butt line, which resulted in the lack of the stirring.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.3
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• pp.29-35
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• 2020

This paper studies the main parameters of tube-to-bar dissimilar material and shape friction welding for piping materials. The weldability of joint parts was investigated with respect to tensile tests, micro-Vickers hardness, the bond of area, and optical microstructure. The specimens are tested as-welded. Optimal welding conditions are n = 2000 rpm, HP = 50 MPa, UP = 100 MPa, HT = 5 sec, and UT = 10 sec when the metal loss (Mo) is 11 mm. Moreover, the same two materials for friction welding are strongly mixed with a well-combined structure of micro-particles without any molten material, particle growth, or defects. Therefore, the expected result of dissimilar material friction welding includes a reduction of cost and material in the welding process.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.116-125
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• 2018

Modified 9Cr-1Mo ferritic steel is a preferred material for steam generators in nuclear power plants for their creep strength and good corrosion resistance. Austenitic stainless steels, such as type 316LN, are used in the high temperature segments such as reactor pressure vessels and primary piping systems. So, the dissimilar joints between these materials are inevitable. In this investigation, dissimilar joints were fabricated by the Shielded Metal Arc Welding (SMAW) process with Inconel 82/182 filler metals. The notch tensile properties and Charpy V-notch impact toughness properties of various regions of dissimilar metal weld joints (DMWJs) were evaluated as per the standards. The microhardness distribution across the DMWJs was recorded. Microstructural features of different regions were characterized by optical and scanning electron microscopy. Inhomogeneous notch tensile properties were observed across the DMWJs. Impact toughness values of various regions of the DMWJs were slightly higher than the prescribed value. Formation of a carbon-enriched hard zone at the interface between the ferritic steel and the buttering material enhanced the notch tensile properties of the heat-affected-zone (HAZ) of P91. The complex microstructure developed at the interfaces of the DMWJs was the reason for inhomogeneous mechanical properties.

• Proceedings of the KWS Conference
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• 2005.11a
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• pp.189-191
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• 2005

Dissimilar joining of AI 6013-T4 alloys and austenite stainless steel was carried out using friction stir welding technique. Microstructures near the weld zone and mechanical properties of the joint have been investigated. Microstructures in the stainless steel side and AI alloy were depended on the thermo-mechanical condition which they received. TEM micrographs revealed that the interface region was composed of the mixed layers of elongated stainless steel and ultra-fine grained AI alloy and intermetallic compound layer which was identified as the $Al_{4}Fe$ with hexagonal close packed structure. Mechanical properties were lower than those of 6013 AI alloy base metal, because tool inserting location was deviated to AI alloy from the butt line, which resulted in the lack of the stirring.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.77-82
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• 1999

The compleete joining method for dissimilar hot die punch materials and its real-time evaluation method are not available at present. Brazing method has been used for joining them, but it is known that the welded joint by the brazing has the lower bonding efficiency and reliability than the diffusion welding. The friction wleding with a diffusion mechanism in bonding was applied in this study. So, this work was carried out to determine the optimal friction welding conditions and to analyze mechanical properties of friction welded joints of hot die punch materials (STD61 for the blade part of hot die punch) to alloy steel (SCM440 for the shank park of hot die punch) such as plunger. In addition, acoustic emission test was carried out during friction welding to evaluate the weld quality.

• Journal of Welding and Joining
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• v.31 no.6
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• pp.58-64
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• 2013

Several joining methods involving resistance welding, laser welding, ultrasonic welding and mechanical joining are currently applied in manufacturing lithium-ion batteries. Cu and Al alloys are used for tab and bus bar materials, and laser welding characteristics for these alloys were investigated with similar and dissimilar material combinations in this study. The base materials used were Al 1050 and oxygen-free Cu 1020P alloys, and a disk laser was used with a continuous wave mode. In bead-on-plate welding of both alloys, the joint strength was higher than the strength of O tempered base material. In overlap welding, the effect of welding parameters on the tensile shear strength and bead shape was evaluated. Tensile shear strength of overlap welded joint was affected by interfacial bead width and weld defect formation. The tensile-shear specimen was fractured at the heat affected zone by selecting proper laser welding parameters.

• Journal of Powder Materials
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• v.20 no.4
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• pp.302-307
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• 2013

A5J32-T4 and A5052-H32 dissimilar aluminum alloy plates with thickness of 1.6 and 1.5 mm were welded by friction stir lap welding (FSLW). The FSLW were studied using different probe length tool and various welding conditions which is rotation speed of 1000, 1500 rpm and welding speed of 100 to 600 mm/min and material arrangement, respectively. The effects of plunge depth of tool and welding conditions on tensile properties and weld nugget formation. The results showed that three type nugget shapes such as hooking, void, sound have been observed with revolutionary pitch. This plunge depth and material arrangement were found to effect on the void and hooking formation, which in turn significantly influenced the mechanical properties. The maximum joint efficiency of the FSLWed plates was about 90% compared to base metal, A5052-H32 when the A5052-H32 was positioned upper plate and plunge depth was positioned at near interface between upper and lower plates.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.2 s.173
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• pp.438-448
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• 2000

Mechanical press joining technique has been used in sheet metal joining processes because of its simple process and possibility of joining dissimiliar metals, such as steel and aluminum. The static and cyclic behavior of single overlap AI-alloy and steel(SPCC) joints has been investigate. Relationships were developed to estimate the strength of the joint taking into consideration base metal strength properties and the geometry of the joint. Fatigue test results have shown that fatigue resistance of the SPCC mechanical press joints is almost equal to that of the spot weld at the life of $10^6$ cycles. Also, the dissimilar material jointed specimen with upper SPCC plate and button diameter corresponding to the nugget diameter of the spot welded specimen has almost same strength as the same material jointed specimen and as the spot welded specimen.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.6
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• pp.652-657
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• 2009

MPW(Magnetic Pulse Welding) is a technologies for welding of metals by means of repulsive force on account of the interaction between electro-magnetic field of coil and current induced in outer pipe. These MPW is one of the most useful welding process of welding ability of the dissimilar metal in which cylindrical materials, such as pipe, tube. As the quality of a weld joint is strongly influenced by process parameters during the welding process and the success of the welding to evaluated according to the leakage pressure. Generally, the process parameters is magnetic pressure, the gap between outer pipe and inner pipe, and the ratio of thickness to diameter of pipe(D/T) in MPW. Therefore, the goal of this study was to explain the effect of parameters on the weld joint leakage pressure. For these purposes, FFD(Fractional Factorial Design) were used for the experiment. The measured data were analyzed by regression analysis and verification experiments with random condition were conducted to confirm the suggested experimental model.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.171-173
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• 2005

To evaluate the applicability of dissimilar metal friction stir welding in automobile manufacturing process, friction stir welding trials were carried out for typical 5000 and 6000 series aluminum alloy sheets with 2mm thickness. The sound joints of A15052 and A16061-T6 alloys were successfully formed under a wide range of welding condition. Excellent weld ability has been obtained at a condition of rotating speed 2000rpm and travel speed 100mm/min, while a radiographic test also confirmed defect free joint for this condition. Through the Erichsen cup test, the plastic formability of the FSWelded joints was found to be about 83% of base metal.