Multi-Objective Parametric Optimization of Weld Strength of Metal Inert Gas (MIG) Welding by using Analysis of Variance, Taguchi, and VIKOR Techniques

Welding is an enormously essential manufacturing technique which allows the users to create permanent joints efficiently, due to its durability this process is extensively used in various industries like automotive, construction as well as in the aviation industry. The present study focuses on the optimization of the Metal Arc Welding using VIKOR method. Four input variables Current, Voltage, Wire Feed Rate and Gas Flow Rate are considered to study their effect on three responses tensile, bending and hardness on the weldments of AISI 1008 low carbon steel material. Experiments were planned as per Taguchi‘s L9 OA. As traditional Taguchi method is not adequate to solve multi responses problem, to overcome this limitation MCDM approach VIKOR analysis has been carried out for obtaining optimal parameters setting for multi-response optimization. Three specimens (for tensile, bending, and hardness) for each experimental run are fabricated for the measurement of respective strength and hardness. Investigation is done by following the steps of VIKOR method, and optimal parameter setting for multi quality response is obtained corresponding to the lower VIKOR index value. Keywords: Metal Inert Gas (MIG) Welding, VIKOR, S/N ratio, ANOVA

MIG and TIG Joining of AA1070 Aluminium Sheets with Different Surface Preparations

In this work, AA1070 aluminium alloy sheets are joined using TIG and MIG welding after three different edge preparations. Shearing, water jet and plasma-cut processes were used to cut sheets, subsequently welded using ER5356 and ER4043 filler metals for TIG and MIG, respectively. Mechanical properties of the obtained sheets were assessed through tensile tests obtaining a relation between sheet preparation and welding tightness. Micro-hardness measures were performed to evaluate the effects of both welding and cutting processes on the micro-hardness of the alloy, highlighting that TIG welding gives rise to inhomogeneous micro-hardness behaviour. After tensile tests, surface fractures were observed employing scanning electron microscopy to highlight the relation between tensile properties and edge preparations. Fractures show severe oxidation in the water jet cut specimens, ductile fractures and gas porosities.

Test and Analysis of TIG-MIG Hybrid Welding Are

A high-speed camera is used to observe the arc starting and arc stabilization process of the TIG-MIG hybrid welding system. Paschen’s law is used to analyze the path of TIG welding arc breakdown under the condition of the conductive channel provided by the MIG welding arc, and the arc starting process of the double arc hybrid welding is determined. The study found that when the electrode spacing is less than 8.5 mm, two molten pools can form a common molten pool after arc initiation of MIG welding; when the spacing is 10 mm, the two molten pools after arc initiation form a “8” shape; When the distance is 12 mm, there is a low temperature zone between the two arcs, which is separated.

Sustainable Analysis of Process Parameters during MIG Welding of 1018 Mild Steel

The present work analyses MIG in terms of strength and consumption of energy during joining of similar AISI 1018 Mild Steel plates. Sustainable manufacturing is the creation of various manufactured products that generally use different processes that will minimize negative impact on environment, conserve natural resources and energy, are also safe for the employees, consumers and communities as well as economically sound. Sustainable manufacturing highlights on the necessity of an energy effective process that optimize consumption of energy. AISI 1018 mild steel is extensively used in automotive industries for pins, worms, dowels gears, non-critical tool components etc. Main important output responses are Tensile Strength and energy consumption during MIG Welding Process by taking Current, Travel Speed and Voltage as effective input variables. The main objective is to optimize energy consumption as well as tensile strength also determination of main influential process parameters on energy Consumption and tensile strength by using Taguchi Method. Contour plot has been also shown.

Influence of Preheating Temperature on Changes in Properties in the HAZ during Multipass MIG Welding of Alloy AW 6061 and Possibilities of Their Restoration

Fusion welding of heat-treatable aluminum alloys is generally accompanied by a significant decrease in mechanical properties in the HAZ caused by the dissolution of the hardening phase. The intensity of this decrease in mechanical properties can be reduced by limiting the heat input value. However, this approach is in direct conflict with the principles for welding aluminum and its alloys. Due to the very high thermal conductivity of aluminum alloys, it is necessary to use preheating for thicknesses larger than 5 mm to eliminate non-penetration and cold joints. This paper aims to show the influence of multiple temperature cycles, performed at different preheating temperatures, on changes in the microstructure and mechanical properties. At the same time, the extent to which the original properties of the material can be restored by natural and artificial aging at 160, 175 and 190 °C is also investigated.

Effect of N on corrosion resistance of Fe-Cr-Ni-Mo-Mn alloy

In order to develop the Fe-Cr-Ni-Mo-Mn-N corrosion resistant alloys, analyze the influence of nitrogen on the corrosion resistance of Fe-Cr-Ni-Mo-Mn alloy, adjust the N content in the alloy system, and Flux cored wires with different N content were prepared. They were surfaced on low carbon steel by MIG welding. The phase composition, microstructure and corrosion resistance of the cladding metal were analyzed to studied the effect of N content on the structure and performance of the surfacing metal. The results show that the addition of nitrogen does not change the matrix structure (which is Fe-Ni-Cr austenite), but with the increase of nitrogen content, the precipitation of nitrides （ Cr2(C,N) and BN ） is