The Experts below are selected from a list of 142071 Experts worldwide ranked by ideXlab platform
Y. Gao - One of the best experts on this subject based on the ideXlab platform.
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The Metal Transfer behavior and the effect of arcing mode on Metal Transfer process in twin-arc integrated cold wire hybrid welding
The International Journal of Advanced Manufacturing Technology, 2016Co-Authors: T. Xiang, H.l. Wei, Huang Can, Y. GaoAbstract:In response to the demands of high-efficient welding, twin-arc integrated cold wire hybrid welding technology was proposed in this paper. In order to realize a stable welding process, the research was focused on the effect of welding electrical parameters on the Metal Transfer process of simultaneous arcing to find a proper range of process parameters. In addition, the experimental research found a new factor to affect the Metal Transfer mode, i.e., arcing mode, and its effect mechanism was discussed in greater detail. The results showed that both the leading wires kept simultaneous arcing with in-phase pulse currents supplied to two wires. The Metal Transfer modes were divided into two types: one is one droplet per pulse, and the other is one droplet multiple pulses, which highly depended on arc voltage. At first, the main Metal Transfer was one droplet multiple pulses at lower arc voltage. Then the Metal Transfer mode started to change to one droplet per pulse with the increase of arc voltage. Finally, when arc voltage continuously increased to a certain value, one droplet multiple pulses once again occurred. This was mainly because the great increase of arc length restricted the expansion of arc root. What is more important, through the comparison between the Metal Transfer processes of simultaneous arcing and alternative arcing, it was found that the arcing mode had a significant effect on the Metal Transfer mode, and the main reason was the arcing mode affected the electric field intensity of arc column.
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Arc characteristics and Metal Transfer behavior of twin-arc integrated cold wire hybrid welding
The International Journal of Advanced Manufacturing Technology, 2016Co-Authors: T. Xiang, H.l. Wei, Y. GaoAbstract:Twin-wire arc served as a high-efficient technology has been fully developed and widely used in the manufacturing industry. In order to further increase welding deposition rate, a novel high-efficient welding system entitled twin-arc integrated cold wire hybrid welding was proposed in this paper. The study focuses on the effect of welding electrical parameters on alternative arcing and Metal Transfer process for the purpose of optimizing electrical parameters to realize a stable welding process. Characteristics of the Metal Transfer processes and the influence mechanism of welding electrical parameters on Metal Transfer modes were studied. The results showed that the two leading wires kept regularly alternative arcing with the phase difference of 180° between the pulse currents supplied to wires, and the alternating frequency increased with arc voltage and welding current. Besides, the Metal Transfer modes were divided into three types by varying welding parameters: short circuiting Transfer, projected Transfer, and streaming Transfer. What is more important, the Metal Transfer mode highly depended on arc length, which was determined by arc voltage when welding current was kept constant. The Metal Transfer mode would change from short circuiting Transfer to projected Transfer, and then converted into streaming Transfer eventually with the increase of arc voltage.
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Numerical simulation of Metal Transfer process in tandem GMAW
The International Journal of Advanced Manufacturing Technology, 2013Co-Authors: Xueping Ding, Lijun Yang, Y. GaoAbstract:A numerical model based on fluid dynamics theory and electromagnetic theory is developed to simulate the dynamic Metal Transfer process in tandem gas Metal arc welding (T-GMAW). The relationship between welding current and surface tension coefficient is modified by analysis of regression in this model. The numerical simulation of the Metal Transfer process in T-GMAW is compared with that in single-wire gas Metal arc welding (SW-GMAW). It is found that a droplet Transfers axially in SW-GMAW, but the droplets Transfer non-axially in T-GMAW. To verify the accuracy of simulated results, the welding experiments were performed in which the actual Metal Transfer processes were recorded by high-speed photography. The simulated results are in good agreement with the experimental ones. This Transfer behavior in T-GMAW is analyzed by studying the distributions of physical quantities including pressure, velocity, and electric potential of the droplet. The simulated results reveal that the electromagnetic force between two droplets results in the different Metal Transfer process. With the increase of the welding current, the surface tension coefficient decreases and the electromagnetic force increases. As a consequence, the Metal Transfer process in T-GMAW is accelerated.
Cuirong Liu - One of the best experts on this subject based on the ideXlab platform.
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Metal Transfer in submerged arc welding
Journal of Materials Processing Technology, 2017Co-Authors: Yanjun Zhu, Cuirong LiuAbstract:Abstract The movement of molten Metal at the wire end in submerged arc welding (SAW) was filmed by a high-speed video camera through a preset tunnel, the welding electric signal was acquired simultaneously. A physical modeling experiment was carried out to simulate the Metal Transfer in SAW. Welding electric signal shows that the stability of welding process is higher at medium current, but it could not reflect the Metal Transfer behavior completely. Combining high-speed videos for welding and physical modeling experiment, it is suggested that there might be three Metal Transfer modes with the increase of welding current, which in turn are: repelled globular Transfer without short-circuit, flux-wall guided Transfer without short-circuit and flux-wall guided Transfer with short-circuit. Analysis result suggests that the arc would always burn even when short-circuit is ongoing in high-current SAW, which is quite different from the short-circuit in gas Metal arc welding (GMAW).
S. Muthukumaran - One of the best experts on this subject based on the ideXlab platform.
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Study of sub-shoulder tool wear on friction stir welded steel plates using two modes of Metal Transfer phenomenon
The International Journal of Advanced Manufacturing Technology, 2015Co-Authors: A. Pradeep, S. MuthukumaranAbstract:Tool wear study is undertaken with IS 3039, grade II steel plates and analysed by two modes of the Metal Transfer phenomenon. The first mode of Metal Transfer takes place by the direct contact of the tool shoulder on the work plate, generating heat owing to friction, and the second mode of Metal Transfer takes place around the pin. This study is aimed at knowing the formation of a weld for every 300-mm length, which indirectly reflects the effect of the pin profiles on producing a better weld. The individual contribution of two modes of Metal Transfer has been studied, and it was observed that the higher the area of the first mode of Metal Transfer, the more the strength of the weld. The variations in the distribution of hardness along the first mode of Metal Transfer were found to be higher, because the compaction offered by the tool shoulder is more than that in the second mode of Metal Transfer. Microstructure and macrostructural analyses were performed on the weld, based on the two modes of the Metal Transfer phenomenon. The ultimate tensile strength gets reduced, if the percentage formation of the first mode of Metal Transfer is less.
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Two modes of Metal Transfer phenomenon in friction stir welding of low alloy steel plates
Proceedings of the 1st International Joint Symposium on Joining and Welding, 2013Co-Authors: A. Pradeep, S. MuthukumaranAbstract:The Metal flow in friction stir welding (FSW) takes place by two modes - The first mode of Metal Transfer takes place by tool shoulder and the second mode by the tool pin. A small quantity of Metal is Transferred from the front side to rear side as layer one over the other for every rotation of the tool. The first mode offers compactness to the weld and is responsible for defect free weld formation. Remaining Metal passes around the pin as a second mode of Metal Transfer. Recent advances in welding are focused on FSW of steels. In this study, the two modes of Metal Transfer phenomenon are analyzed to understand the formation of FSW of steels. The first mode of Metal Transfer increases the compactness of the weld and eliminates defects. An increase in the first mode of Metal Transfer improves the tensile properties. There exists a linear correlation between the percentage of first mode in the fractured surface and the ultimate tensile strength. Micro hardness measurement showed higher value at both stir zone and HAZ compared to base Metal due to grain refinement. At 1400 rpm tool rotation speed the tensile specimen is found to fail at the base material. Hence, maximum possible strength has been achieved.
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Analysis of first mode of Metal Transfer in friction stir welded plates by image processing technique
Journal of Materials Processing Technology, 2007Co-Authors: Preetish Sinha, S. Muthukumaran, S.k. MukherjeeAbstract:Abstract The Metal flow phenomenon in friction stir welding (FSW) comprised of two modes of Metal Transfer. The first mode of Metal Transfer taking place layer by layer and is caused by the shearing action of the tool shoulder, while the second mode is caused by the extrusion of the plasticized Metal around the pin. The aim of the present study is to quantitatively determine the amount of Metal Transferred by the first mode and its effect on strength of the weld. The images of the fractured faces of the samples are captured and processed to identify and distinguish the two modes of Metal Transfer. Quantitative analysis of the fractured surface and reveals existence of a possible linear correlation between the first mode in the fractured surface and the ultimate tensile strength, which controls the presence of defect in the weld.
Ding Nian - One of the best experts on this subject based on the ideXlab platform.
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Metal Transfer of aluminum alloy double-wire pulsed GMAW with a median waveform
Journal of Materials Processing Technology, 2020Co-Authors: Zhan Jiatong, Min Zeng, Cao Xuanwei, Ding NianAbstract:Abstract This paper proposes a double-wire pulsed gas Metal arc welding (GMAW) process with a median current waveform based on traditional double-wire pulsed GMAW. A high-speed digital camera and digital oscilloscope were used to simultaneously record the Metal Transfer process as well as the voltage and current waveforms under different median currents. The median pulse was modeled as an exponential function and a mathematical model of the droplet diameter was established. Further, variation of the output current during the welding process and the influence of pulse parameters on the Metal Transfer process were accurately described. The results show that the median current has a significant impact on the Metal Transfer process. When the median current increases, the Metal Transfer period gradually decreases and the desired one drop per pulse (ODPP) mode, with a moderate droplet size and no droplet collision, is almost achieved within an appropriate median current range. As the median current gradually increases, the droplet diameter also increases but then begins to decrease as the median current further increases and gets closer to the peak current. The droplet offset distance first decreases considerably, then begins to increase, and droplet collision occurs as the median current continues to increase, resulting in an unstable Transfer process. Initially, the Transfer time decreases and then increases, followed by a subsequent decrease as the median current continues to increase.
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Effect of phase on the behavior of Metal Transfer in double-wire pulsed GMAW
The International Journal of Advanced Manufacturing Technology, 2018Co-Authors: Yin Tong, Ding Nian, Min Zeng, Zhuoyong LiangAbstract:High-speed photography was used to record Metal Transfer during double-wire pulsed gas Metal arc welding (GMAW) in the synchronous, alternating and independent phases, while the voltage and current waveforms were recorded simultaneously. According to the relationships between voltage, current, and Metal Transfer, the effect of phase on the behavior of Metal Transfer was analyzed. The experimental results demonstrated that Metal Transfer was all a “one drop per pulse” (ODPP) spray Transfer mode in the three phases. ODPP was easier to achieve and Metal Transfer was more stable in the alternating phase. The deviation distance of droplets in the synchronous phase was larger than that in the alternating and independent phases, and the deviation distance of droplets in the alternating phase was minimum. The surfaces of weld beads acquired showed a desirable weld bead appearance that resembled fish scales. The weld bead in the alternating phase exhibited more obvious fish scales. Phase had little effect on weld width and reinforcement, though it had a significant effect on penetration. Penetration in the alternating phase was significantly deeper than penetration in the synchronous or independent phases, and penetration was minimum in the synchronous phase. The alternating phase facilitated the growth of columnar grains to be inhibited and the directions of ferrites to be disrupted. The columnar grains were discontinuous and the directions of ferrites were more chaotic in the alternating phase when compared with in the synchronous phase. And the anisotropic microstructure in the independent phase was between the synchronous and alternating phases.
Yanjun Zhu - One of the best experts on this subject based on the ideXlab platform.
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Metal Transfer in submerged arc welding
Journal of Materials Processing Technology, 2017Co-Authors: Yanjun Zhu, Cuirong LiuAbstract:Abstract The movement of molten Metal at the wire end in submerged arc welding (SAW) was filmed by a high-speed video camera through a preset tunnel, the welding electric signal was acquired simultaneously. A physical modeling experiment was carried out to simulate the Metal Transfer in SAW. Welding electric signal shows that the stability of welding process is higher at medium current, but it could not reflect the Metal Transfer behavior completely. Combining high-speed videos for welding and physical modeling experiment, it is suggested that there might be three Metal Transfer modes with the increase of welding current, which in turn are: repelled globular Transfer without short-circuit, flux-wall guided Transfer without short-circuit and flux-wall guided Transfer with short-circuit. Analysis result suggests that the arc would always burn even when short-circuit is ongoing in high-current SAW, which is quite different from the short-circuit in gas Metal arc welding (GMAW).