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In this paper, a two-directional automated machine with a controller for flat gas metal arc welding is developed for welding along any complex shape. Consistent and uniform weld bead deposition can...

Three different pre-treatment methods, that is, alkali hornification, water hornification, and alkali treatment, are evaluated for the improvement in durability of agave natural fiber-reinforced po...

In this work, a bi-directional automatic movement unit for planar welding is indigenously developed in order to obtain weld with uniform bead width along a desired path. System modeling of ...

Experimental and numerical investigations are performed to assess the durability of Palmyra natural fiber composites under hydrothermal ageing conditions. The effect of alkali and stearic acid pret...

Keeping in view the role of heat generation and dissipation, the aim of this work is to develop a thermal model for the twin-tube hydraulic shock absorber using bond graph approach. In this paper, ...

In the present work, a simple arrangement is made to provide double layer shielding gas supply in addition to primary shielding during gas metal arc welding (GMAW) of two dissimilar stainless steels, i.e., AISI 316 and duplex 2205. Influences of double layer shielding in addition to five more process parameters like welding current, voltage, material of the electrode wire, the type of primary shielding gas, and flow rate on joint tensile strength and fusion zone microhardness are studied. An experimental design technique is used to design the experimental conditions and the results are analyzed to observe the influences of each process parameter and their interactions. The tensile strength is more influenced by the electrode material and the type of shielding, whereas current, interaction between current × voltage and current × flow rate significantly influence microhardness. Welding voltage influences both tensile strength and microhardness. Double layer shielding with CO2 as an outer shielding layer hel...

In the present paper three dimensional cutter deflections and the corresponding profile errors during end milling are predicted by finite element and bond graph modeling approach. The deflections have been modeled considering the cutter as a cantilever beam fixed at the collet end. Rayleigh beam model is used for modeling to consider the shear force effect, and Castigliano's theorem of strain energy is used to predict the deflections due to radial, tangential, and axial cutting forces. The tool-workpiece contact region is sliced into small elements to apply the forces on the entire contact region and predict deflections more accurately. The predicted deflections at different parametric settings are compared with experimental measurements by measuring the geometric accuracy of the cut profiles. The depth of cut has the most significant influence on profile deviations, while feed and speed have marginal effects. The results reveal that the predictions by finite elements and the bond graph closely matches wi...

In tungsten inert gas (TIG) welding, limited depth of penetration can be achieved during single pass welding. To achieve the desired depth of penetration, the speed of welding needs to be significantly reduced and hence, the productivity decreases. In the present work, the effect of TiO2 activated flux on penetration is evaluated for different workpieces namely AISI 1020, AISI 304, AISI 316, and Duplex 2205 steels at different currents and shielding gas compositions. The results show a significant increase in the depth of penetration and reduction in the width-to-penetration ratio using the activated flux for all the workpiece materials considered here. Current increases the depth of penetration, however, the influence of flux becomes more significant with higher welding current. Maximum of 37.8%, 44.3%, 47%, and 124% increase in depths of penetration is measured for AISI 1020, AISI 304, AISI 316, and Duplex 2205 steels, respectively, when activated flux is used. Also, maximum of 70% increase in the depth...

In the present work, the influence of heat input is studied on depth of penetration while depositing bead on AISI 304 stainless steel using an indigenously fabricated automatic gas metal arc welding (GMAW) movement setup. Depth of penetration and fusion zone profiles are predicted at different conditions by the bond graph modeling approach and validated using measured depth of penetration and fusion profile. The effects of heat input on toughness and metallurgical behavior are analyzed while joining AISI 304 plates using automatic GMAW. Heat input and gas flow rate significantly influence the toughness at room temperature and at −20°C. Metallurgical observations by scanning electron microscopy are carried out and it is observed that high heat input and lower cooling rate increase grain size. High heat input and rapid cooling prevent grain growth and lead to grain refinement.

Gas metal arc welding (GMAW) offers highly efficient and low-cost welding, but manual movement of torch affects the uniformity of bead geometry, penetration, and heat input. In the present work, an indigenous automatic movement setup is designed and fabricated for GMAW. System behaviors like drive motor response, carriage, and wheel movement are studied through bond graph modeling. Welding time and welding velocity obtained from simulation are used to obtain the deposition efficiency during weld bead deposition on low carbon steel and stainless steel workpieces. Spatter index is also calculated for both the materials. Welding performance of automatic welding is compared with manual movement welding, and automatic welding is found capable to offer high deposition efficiency, low spatter index, uniform depth of penetration, and lower distortion for both the materials. Variation in microhardness and metallurgical observations by scanning electron microscopy are carried out for microstructure analysis.