scholarly journals The Study on Feasibility and Welding Characteristics of GMAW Surfacing Remanufacturing of H13 Steel Cutter Ring of TBM Hob

Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1559
Author(s):  
Moyun Zhang ◽  
Shihai He ◽  
Boyan Jiang ◽  
Xuming Yao ◽  
Kui Zhang

As H13 steel is a common material for cutters of Tunnel Boring Machine (TBM), the research on surfacing remanufacturing performance is of great value. In this paper, the phase composition of the surfacing layer of H13 steel after gas metal arc welding (GMAW) was analyzed by exploring the precipitation of hard phase in the molten pool, and the microstructure evolution of the surfacing layer was revealed. Then, we carried out simulation modeling analysis on H13 steel surfacing remanufacturing. Results show that: (1) the surfacing layer is combined with the base metal by physical metallurgy without obvious defects such as pores, inclusions and cracks in the surfacing layer; (2) the hardness of the surfacing layer is 60 HRC, which is about 1.5 times of that of the base metal; (3) the stress is mainly concentrated in the arc starting and ending points, followed by the external constraints on both sides of the surfacing layer; (4) the deformation of surfacing layer is slight, which does not affect the forming quality of base metal, while the deformation of base metal is relatively severe. This paper verifies the feasibility of H13 steel remanufacturing from experimental and simulation, providing theoretical basis for future engineering practice.

Author(s):  
Emre Korkmaz ◽  
Cemal Meran

In this study, the effect of gas metal arc welding on the mechanical and microstructure properties of hot-rolled XPF800 steel newly produced by TATA Steel has been investigated. This steel finds its role in the automotive industry as chassis and seating applications. The microstructure transformation during gas metal arc welding has been analyzed using scanning electron microscope, optical microscope, and energy dispersive X-ray spectrometry. Tensile, Charpy impact, and microhardness tests have been implemented to determine the mechanical properties of welded samples. Acceptable welded joints have been obtained using heat input in the range of 0.28–0.46 kJ/mm. It has been found that the base metal hardness of the welded sample is 320 HV0.1. On account of the heat-affected zone softening, the intercritical heat-affected zone hardness values have diminished ∼20% compared to base metal.


2007 ◽  
Vol 129 (6) ◽  
pp. 991-999 ◽  
Author(s):  
Kehai Li ◽  
YuMing Zhang

Gas metal arc welding (GMAW) is the most widely used process for metal joining because of its high productivity and good quality, but analysis shows that the fundamental characteristic restricts conventional GMAW from further increasing the welding productivity. A novel GMAW process, refereed to as double-electrode GMAW or DE-GMAW, thus has been developed to make it possible to increase the melting current while the base metal current can still be controlled at a desired level. This fundamental change provides an effective method to allow manufacturers to use high melting currents to achieve high melting speed and low base metal heat input. A series of experiments have been conducted to uncover the basic characteristics of this novel process. Results obtained from analyses of high-speed image sequences and recorded current signals suggest that DE-GMAW can lower the critical current for achieving the desired spray transfer, shift the droplet trajectory, reduce the diameter of the droplet, and increase the speed and (generation) rate of the droplets.


2011 ◽  
Vol 268-270 ◽  
pp. 24-29 ◽  
Author(s):  
Ming Liang Wu ◽  
Jian Kang Huang ◽  
Ri Hong Han ◽  
Yu Shi

DE-GMAW (Double-Electrode Gas Metal Arc Welding) is a new welding technology. It is possible to change the melting current while the base metal current still be controlled at a desired level because the changed part of the melting current would be bypassed without flowing through the workpiece. So the heat input of base metal can be controlled accurately in DE-GMAW, and this welding method is suitable for dissimilar metal welding which has strict requirements for heat input of base metal, such as joining of steel and aluminum. On the basis of heat source model of DE-GMAW, numerical simulation and analysis on temperature field and residual stress for DE-GMAW in bonding steel and aluminum were done. The results show that residual stress after welding changed sharply from close 0 MPa to about 130 MPa at the interface of aluminum and steel. This value is greater than the binding force of steel, aluminum interface.


2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Wenhao Wu ◽  
Ming Zhao ◽  
Haiyan Wang ◽  
Yanxia Zhang ◽  
Tong Wu

Twin-Wire Pulsed Tandem Gas Metal Arc Welding process with high welding production efficiency was used to join the girth weld seam of API X80 steel linepipe of 18.4 mm wall thickness and 1422 mm diameter. The macrostructure, microstructure, hardness, and electrochemical corrosion behavior of welded joints were studied. Effects of temperature and Cl− concentration on the corrosion behavior of base metal and weld metal were investigated. Results show that the welded joint has good morphology, mechanical properties, and corrosion resistance. The corrosion resistance of both the base metal and the weld metal decreases with increasing temperature or Cl− concentration. In the solution with high Cl− concentration, the base metal and weld metal are more susceptible to pitting. The corrosion resistance of the weld metal is slightly lower than that of the base metal.


Author(s):  
Jun Zhou ◽  
Mohammad S. Davoud ◽  
Hai-Lung Tsai

Arc welding is generally used to join thick metals in many engineering applications. However, poor penetration often occurs due to arc heat diffusion into the base metal. Hence, arc welding of thick metals normally requires grooving and/or preheating of the base metal and sometimes requires multiple passes for very thick metals or metals with high conductivity, such as aluminum alloys. In gas metal arc welding of thick metals with grooves and preheating, complicated melt flow and heat transfer are caused by the combined effect of droplet impingement, gravity, electromagnetic force, surface tension, and plasma arc pressure. Understanding these complicated transport phenomena involved in the welding process is critical in improving the penetration depth and weld quality. In this study, mathematical models and associated numerical techniques have been developed to study the effects of grooves and preheating on melt flow, diffusion of species, and weld penetration in gas metal arc welding of thick metals. Complex melt flow, transient weld pool shape and distributions of temperature and species in the weld pool are calculated. The continuum formation is adopted to handle liquid region, mushy zone and solid region. VOF technique is used to handle transient deformed shape of weld pool surface. The preliminary results show both grooves and preheating have important effects on the melt flow in weld pool and the weld penetration. Computer animations showing the evolutions of temperature; melt flow; and the interaction between droplets and weld pool will be presented.


2013 ◽  
Vol 395-396 ◽  
pp. 1114-1117 ◽  
Author(s):  
Ming Zhu ◽  
Yu Shi ◽  
Ding Fan ◽  
Hai Zhou

A novel and high efficient consumable double-electrode gas metal arc welding (consumable DE-GMAW) method has been introduced. Because of the coupled welding parameters, a multi-input multi-output (MIMO) control scheme was proposed and tested, which controlled the bypass arc by adjusting the bypass wire feed speed, and controlled the base metal current by adjusting the bypass current. Then, the welding experiment has been carried out. The results showed that the MIMO control scheme was effective. The base metal current was controlled at a nearly constant level and the welding process was stable. Also a good weld appearance was obtained.


2018 ◽  
Vol 773 ◽  
pp. 189-195 ◽  
Author(s):  
Kittipong Kimapong ◽  
Surat Triwanapong

In this paper, experiments on welding a dissimilar SS400/SUS304 steel T-fillet joint using high chromium electrode, and an effect of welding current on joint properties were studied. T-joints wielded by the designed specific welding currents were mechanically prepared and systematically investigated for joint properties. The experimental results were summarized as follows. Dissimilar SS400/SUS304 steels T-fillet joint could be successfully welded using a gas metal arc welding process with no defect in a weld metal. The optimized welding current in this experiment was 160 A that showed the least crack length of 0.247 mm. from a bending test. A different chemical composition of low carbon steel and high chromium weld metal produced a small interface shown with a smaller mixed zone of reinforced elements and base metal. It was also affected to decrease in the joint strength. However, the increase in the welding current could increase a combination of reinforced elements and a base metal on the interface, and it showed an effect to increase in the joint strength.


2020 ◽  
Vol 140 (3) ◽  
pp. 320-325
Author(s):  
Yoshihiro Ohnishi ◽  
Takahisa Shigematsu ◽  
Takuma Kawai ◽  
Shinichi Kawamura ◽  
Noboru Oda

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