http://localhost:8081/jspui/handle/123456789/122 Sun, 06 Jul 2025 10:21:10 GMT 2025-07-06T10:21:10Z http://localhost:8081/jspui/handle/123456789/17732 Title: ANALYSIS AND DESIGN OF COOLING CHAMBER FOR GAS ATOMIZATION PLANT Authors: Sharma, Pankaj Abstract: The spray forming process is the process in which a molten metal is impinged by inert gases which results in atomized droplet. The resulting metal droplets while on flight and in residence time inside the spray cone cools rapidly before impinging onto the substrate. The temperature of smaller droplet drops down very fast and strikes the substrate in solid state while larger droplet strike the substrate in liquid form. Therefore to get the mushy droplet impinging on to the substrate knowledge of the thermal history of droplet is of utmost important. In order to determine the size of the cooling chamber of gas atomization plants, a fundamentally based mathematical model was described and the governing differential equation was solved using mathematically modeling method, and the relation between the flight distance and the time was established, then it is solved with the help of initial and boundary condition. With the help of the atomizer angle the size of the cooling chamber is calculated by the help of trigonometry. Fri, 01 May 2015 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/17732 2015-05-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/17729 Title: WEAR STUDY ON SOME BOILER STEELS Authors: Kalra, Ankit Abstract: Erosion wear of three boiler steels: SA 210 Al, SA 213 Til, SA 213 T22, was examined using TR-470 air jet erosion tester and alumina as the erodent at the particle velocity of 30 m/s and the impact angles of 300and 90°. The test was conducted at different angle to know the effect of angle of impingement at the surface of component of boiler and it was found that more wear takes place at small angle. A steady state erosion wear was reached in the test conducted which was further used to compare the three steels. Among the studied boiler steels material loss was maximum for SA 210 Al steel. Another test which was conducted to study the erosive behaviour of the above three steels was slurry erosion wear test. Slurry erosion wear test was performed to examine steels using sand particles, used for preparing boiler bed, as erodent. Results of slurry erosion test verify results of air jet erosion test. Fri, 01 May 2015 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/17729 2015-05-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/17724 Title: STUDIES ON ADHESIVE JOINING OF COPPER USING NANO-COMPOSITE ADHESIVE Authors: Patel, Avantika Abstract: Effect of well dispersed nano particles filled epoxy based adhesive prepared by innovative ultrasonic dual mixing on lap joint of copper was investigated. The composite adhesive containing 1, 3, and 5 vol. % of about 30±5 rim size hO2 used to prepared adhesive joints. The lap shear joint of the composite adhesive are characterized by their Lap shear strength as a function of bond line thickness as well as amount of filler. Nano particles filled epoxy adhesive joints was compared with neat epoxy joints in respect to its bond strength and durability. The bond line thickness of the adhesive with respect to amount of nano TiO2 filler has been optimized for maximum tensile lap shear strength of mechanically and chemically treated copper substrate. Copper have tendency to form brittle amine compound when amine hardener is used as a curing agent. To avoid that, a barrier layer is over the copper surface by using different types of chemical treatment. Chemically treated copper joint with composite adhesive shows higher lap shear strength as compare to mechanically treat copper joint with neat epoxy. FeCl3 type of chemical treatment shows better result as compare to other types of chemical treatment with respect to lap shear strength of joint. Fri, 01 May 2015 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/17724 2015-05-01T00:00:00Z http://localhost:8081/jspui/handle/123456789/17722 Title: THERMAL STABILIZATION OF NANOCRYSTALLINE Fe-Cr ALLOYS DEVELOPED BY MECHANICAL ALLOYING Authors: L, Hari Babu Abstract: This work examines the influence of insoluble alloying element Y (up to 1 at.%) on the thermal stability of nanocrystalline Fe-Cr alloys prepared by mechanical alloying (MA). The ball milled samples were subjected to isochronal heat treatments up to 1200°C. Crystallite size based on Xray diffraction (XRD) analysis along with microhardness measurements were carried out to investigate their thermal stability, Microstructural evolutions were analyzed using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The Gibbs free energy change and XRD analysis showed that I at. % Y could be dissolved in Fe-Cr matrix after 25 h of MA. Feasibility of formation of Fe-Cr-Y solid solutions has been explained from the Gibbs free energy change using Miedema's model and Toop's model. Thermodynamic analysis portrayed that the energy barrier required for formation of disordered solid solution exceeded by the supplementary energy produced by strain dislocations energy and grain boundary defects. Grain growth was restricted for alloys with higher Y (1 at.%) content and nanocrystalline grains (within 50 nm) were retained up to 1000°C. Alloys with lower Y% displayed less stability but relatively better than that of the Fe-Cr alloys without Y additions. Grain size analysis by AFM and TEM is well corroborated with XRD crystallite size. The high thermal stability as well as large strengthening effect is discussed in the light of solid solution strengthening due to formation of disorder solid solution, precipitation hardening and grain boundary pinning by solute drag effect and/or segregation of Y. Fri, 01 May 2015 00:00:00 GMT http://localhost:8081/jspui/handle/123456789/17722 2015-05-01T00:00:00Z