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This work is based on a comparative study of the weldments fabricated by Activated Flux Tungsten Inert Gas (A-TIG) welding and autogenous Tungsten Inert Gas (TIG) welding of 10 mm thick Inconel 617 plates. Flux powders used for A-TIG welding were Titanium dioxide (TiO2) and Silicon dioxide (SiO2). Macrostructure and microstructure analyses and characterization of mechanical properties of both A-TIG and TIG weldments were investigated. The microstructure of Inconel 617 was made up of several secondary phases and fine austenitic grains. Mechanical testing carried out in this study included Bend Test, Tensile Test, Vicker's Micro-Hardness Test and Charpy Impact Test at room temperature (RT) and a sub-zero temperature (SZT) of −50 ∘ C. The Bend test was found satisfactory for both A-TIG and TIG weldments. TIG weldments' tensile strength and microhardness were determined to be 782 MPa and 265.44 HV, respectively. However, it was determined that the base metal had a tensile strength of 756 MPa and that the tensile strength and microhardness of the A-TIG weldment were 707 MPa and 252.73 HV, respectively. The TIG weldment was proved to have the highest tensile strength and microhardness due to the availability of strengthening elements like Molybdenum (Mo) and Chromium (Cr), as carbides in the fusion zone. Impact toughness of the A-TIG weldment was higher than that of the TIG weldment both at room and sub-zero temperatures due to the application of TiO2 as flux and the high heat input during A-TIG welding. The ductile mode of fracture was observed in all weldments. [ABSTRACT FROM AUTHOR]

An experimental study to measure the evaporation rates, engine performance and emission characteristics of cotton seed biodiesel (cotton seed oil methyl ester) and its blends in different volumetric proportions with diesel is presented. The thermo-physical properties of all the fuel blends have been measured and presented. Evaporation rates of neat cotton seed biodiesel, neat diesel and their bends have been measured under slow convective environment of air flowing with a constant temperature. Evaporation constants have been determined by using the droplet regression rate data. The neat fuels and fuel blends have been utilized in a test engine with different load conditions to evaluate the performance, combustion and emission characteristics of the fuels. The specific fuel consumption values of the two blends, viz. B25 and B75 are found to be same. At the highest load, B0 records the lowest CO volume followed by B100. From the observed evaporation, performance and emissions characteristics, it is suggested that a blend of B50 and B75 can be optimally used in standard diesel engine settings. [ABSTRACT FROM AUTHOR]