Electro-discharge machining (EDM) is one of the advanced non-conventional machining techniques used in industries. Most of the EDM research areas are directed towards the linear movement (up-and-down) of the electrode. Through a novel innovation, an innovative way of machining a curvature channel through a semicircular curved copper electrode is possible through curved EDM process. The experimental setup is developed and installed on the Z -axis numerically controlled(ZNC)EDM machine. The oscillating motion of curved electrode on stationary workpiece is obtained by implementing the concept of mechatronics. In this present work, we attempt to investigate the effect of input machining parameters on the output performance characteristics in curved EDM process. During pilot experimentation, critical variables are identified and selected as sparking current, pulse on time, pulse off time and angular sensitivity. Design of Experiment using Taguchi ( L ₉ ) is used to formulate the planned experiments and to evaluate the effects of input machining characteristics on Material Removal Rate (MRR), Electrode Wear Rate (EWR), Curved Machining Angle (CMA), and Curvature Depth (L). Regression analysis and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) are effectively used to validate the model developed for the curved machining. The results obtained after experimentation predicts that the model can be accepted to optimize the quality machining characteristics in curved EDM process. Geometrical analysis and surface roughness are evaluated for the machined curvature through the advance measuring equipment’s. Scanning Electron Microscopy (SEM) is also used for observing the microstructure at higher magnification of workpiece material before and after machining.

In this study, three different arc welding processes, namely tungsten inert gas (TIG), metal inert gas (MIG) and shielded metal arc welding (SMAW) processes, are used to weld 409 M ferritic stainless steel. K-type thermocouples are located in the area of heat-affected zone by drilling blind holes in a plate at a distance of 3 mm and 7 mm from the weld line, revealing the contours of the temperature distribution of the weld. The experimental results are compared with the results of simulations using ANSYS by Goldak heat source model. The temperature is experimentally measured in the heat-affected region with the help of a thermocouple. The temperature distribution profile by the finite element method using ANSYS is compared with the experimental temperature distribution profile with the heat source. The experimental and simulation results for TIG, MIG and SMAW welding processes have been found to be excellent.

This experimental study investigates the effects of welding low nickel Cr-Mn austenitic stainless steel with gas tungsten arc welding process with and without filler (autogenous) weld by varying the welding currents (120A, 130A and 140A). The microstructural examination of weld has been carried out with optical microscope and mechanical properties with Vickers microhardness and tensile tester. The corrosion behaviour of the welded joints are analysed by double loop electrochemical potentio-kinetic reactivation test to obtain degree of sensitisation. The microstructural examination of welded joints revealed that, as the welding current increases, the inter-dendritic spacing as well as the dendrite size increases. The tensile strength and hardness decrease with increasing welding current for 308 L filler and autogenous weld. The degree of sensitisation increases with increasing welding current for both the welds. The results reveal that the autogenous welds have higher tensile strength, higher hardness and lower degree of sensitisation as compared to welds with 308 L filler.