• Journal of Welding and Joining
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• 제9권1호
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• pp.48-57
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• 1991

Welding of dissimilar materials is an area of growing importance in the automotive, aerospace, electronics medical and other domestic appliance industries. This study investigated the ultrasonic welding of dissimilar polymers. Two amorphous and two semicrystalline polymers were used, utilizing all possible welding combinations. For each combination of dissimilar materials, the weldabilitys of the joint was evaluated as a function of weld time, amplitude of vibration and pressure. The joint was also examined microscopically to analyze the melting and flow of the materials. It was generally around found that welding of amorphus polymers resulted in very poor joints. Welding of the amorphous polymers together and welding of the semicrystalline polymers together produced good joints.

• 열처리공학회지
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• 제34권4호
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• pp.165-170
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• 2021

Zirconium has excellent mechanical strength and high heat resistance and excellent corrosion resistance, and it is very important to study zirconium's dissimilar welding properties since it can be used in various applications under harsh environments. Similar welding of pure zirconium and dissimilar metal welding of pure zirconium and pure titanium were performed by TIG welding, and the welding properties were studied in association with microstructural and mechanical properties. In the Zr/Zr welded specimen, sound FZ and HAZ regions showed a basketweave microstructure composed of plate α phase. FZ region of Zr/Ti dissimilar welded specimen exhibited a maximum hardness value of 354.8 Hv, which is about three times higher than that of Ti base metal, due to the precipitation of very fine metastable ω and α phases in the beta matrix. In addition, due to the microstructural continuity in the FZ and HAZ regions, excellent elongation property of 21% was exhibited.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.110-114
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• 2008

Determination of weld-induced residual stress has been an important issue in nuclear power industry because several failures were reported in dissimilar metal weld parts due to primary water stress corrosion cracking. In this context, a couple of remarkable round robin analyses were conducted to quantify the welding simulation variables and to establish optimized numerical analysis process. The purpose of the present research is to introduce welding simulation results for a safety and relief nozzle, which has a dissimilar metal weld part as well as a similar metal weld part. First, finite element analyses are carried out to calculate residual stresses at the inside of nozzle considering only dissimilar metal welding. Subsequently, residual stresses taking into account both the dissimilar and similar metal welding are computed. The similar metal weld effect is evaluated by compa

• 한국정밀공학회지
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• 제22권8호
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• pp.17-26
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• 2005

Dissimilar-metal welds(DHWs) are used widely in various industrial applications due to the pratical importance from the technical and economic aspect. However, DMWs have several fabricative and metallurgical drawbacks that can often lead to in-service failures. For example, the most pronounced fabrication faults are hot cracks. Recently, DMWs have used the various of heat source to decrease such as faults. In this paper, the weldability on dissimilar metal welds of Austenite stainless steel and Low carbon steel using a continuous wave Nd:YAG laser was experimentally investigated. Experiments were conducted to determine effects of welding parameters, on eliminating or reducing the extent welding zone formation at dissimilar metal welds and to optimize those parameters that have the most influence parameters such as focus length, power, beam speed, shielding gas, and wave length of laser.

• Journal of Welding and Joining
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• 제28권3호
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• pp.36-41
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• 2010

High Mn steel has been developed for automotive applications since the steel has an excellent combination of strength and ductility. However, from the viewpoint of welding, high Mn steel has a few problems related to its chemical composition. This paper describes characteristics of dissimilar $CO_2$ laser welding for expanding application of high Mn steel. From this work it was cleared that dissimilar laser welded joint between high Mn steel and carbon steel had poor formability due to the formation of martensite within weld metal. In order to improve ductility of welded joint, the method of controlling the dilution ratio of high Mn steel was suggested.

• 한국기계가공학회지
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• 제18권7호
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• pp.90-96
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• 2019

Recently, friction stir welding of dissimilar materials are one of the biggest issues in terms of light-weight and eco-friendly technology of the automotive, aircraft and ship industry. In this study, friction stir welding of dissimilar materials is introduced with different tool rotational speed. Materials used in experimentation consist of A357 gravity cast aluminum alloy and FB590 high-strength steel plates. Dissimilar materials of plate type are fabricated with width of 150mm, length of 300mm and thickness of 3mm and welding is carried out by the lap joint method. The correlation between probe length and mechanical properties were investigated according to rotational speed and welding speed at tool tilt angle 0 degree. Consequently, feasibility of FSWed dissimilar materials were successfully presented in case of cast aluminum and high-strength steel at lap joint method.

• Journal of Welding and Joining
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• 제32권1호
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• pp.34-39
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• 2014

There are so many difficulties of melt bonding mainly applied for hull construction of a aluminum alloy small boat. For resolving this problem, Friction stir welding(FSW) in non-melting solid state welding Process generally is applied in the transport industry. This paper is studied the joining strength characteristics and macrostructure according to dissimilar aluminium 5000/6000 alloy joining for a small boat applied for this FSW technology. It is reported that difference of joining strength in accordance with the direction of rotation in case of friction stir welding between dissimilar metals(Al/Cu, Al/Fe) is also highly large. In this study, Test is carried out by making the specimen according to the direction of rotation of dissimilar aluminium alloy joining.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1120-1125
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• 2004

Welding characteristics of STS304 stainless steel and Inconel 600 using a continuous wave Nd:YAG laser are experimentally investigated. Alloy 600 being used in steam generator tubing of pressurized water reactor(PWR) exposed to some corrosion environment, stress corrosion cracking can occur on this material. Presented here are the results from a series of experiments in which dissimilar metal welds were made using the gas tungsten arc welding process with pure argon shielding gas. But It is well known that solidification cracking susceptibility of austenitic alloys depends on the solidification temperature range and amount/distribution of solute rich liquid that exists at the terminal stages of solidification. An experimental study was conducted to determine effects of welding parameters and to optimize those parameters that have the most influence on eliminating or reducing the extent welding zone formation at dissimilar metal welds.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2007년 추계학술발표대회 개요집
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• pp.190-192
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• 2007

High Mn steel has been developed for automotive applications since the steel has an excellent combination of strength and ductility. However, from the viewpoint of welding, high Mn steel has a few problems related to its chemical composition. In this study, development of dissimilar laser welding technology has been investigated for expanding application of high Mn steel. The results have shown that dissimilar weld joint between high Mn steel and carbon steel has poor erichsen property using STS309L filler wire or not.

• Journal of Welding and Joining
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• 제6권1호
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• pp.21-27
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• 1988

This paper describes weldability of dissimilar metal plates with YAG laser for the use of a small-size electronic spring parts. Effects of welding conditions, combination of plates, thickness of upper plate are examined in relation to welding strength and microstructure of welded region. The obtained results are summarized as follows. Welding defects such as cavity and crack showed a tendency to easily occur in the case where 1) pulse duration is short, 2) laser power is high, 3) PBS plate with high thermal diffusivity is used for lower plate. Among these defects, the occurrence of cavity cased a drop of welding strength. This results from the reduction of welding area between upper and lower plates. In SK-5/SUS304 plates (thickness: 0.2/0.4mm/, welding strength was the highest in welding conditions: laser power is 30J/pulse, pulse duration 9ms, amount of defocus +2mm.