{"634265":{"#nid":"634265","#data":{"type":"event","title":"PhD Proposal by Jahnavi Desai","body":[{"value":"\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ETHE SCHOOL OF MATERIALS SCIENCE AND ENGINEERING\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EGEORGIA INSTITUTE OF TECHNOLOGY\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EUnder the provisions of the regulations for the degree\u003C\/strong\u003E\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\n\u003Cstrong\u003EDOCTOR OF PHILOSOPHY\u003C\/strong\u003E\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\n\u003Cstrong\u003Eon Thursday, April 23, 2020\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003E10:00 AM\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003Evia\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cbr \/\u003E\r\n\u003Cstrong\u003EBlueJeans Video Conferencing\u0026nbsp;\u003C\/strong\u003E\u003Ca href=\u0022https:\/\/primetime.bluejeans.com\/a2m\/live-event\/wapzjccp\u0022 target=\u0022_blank\u0022\u003Ehttps:\/\/primetime.bluejeans.com\/a2m\/live-event\/wapzjccp\u003C\/a\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003Ewill be held the\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EDISSERTATION PROPOSAL DEFENSE\u003C\/strong\u003E\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\n\u003Cstrong\u003Efor\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EJahnavi Desai\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003E\u0026quot;In-Situ Optical Microscopy Corrosion Experiments to Study the Influencing Microstructural Parameters on \u0026beta; Precipitation in AA 5456\u0026quot;\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ECommittee Members:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Josh Kacher, Advisor, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Hamid Garmestani, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Preet Singh, MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Mathew McDowell, ME\/MSE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EProf. Chaitanya Deo, MSE\/NRE\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EAbstract:\u003C\/strong\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EAluminum 5xxx series alloys are non-heat treatable, moderate strength wrought alloys with 3-5% of magnesium. They are widely used as structural components for marine, military and other transportation applications due to their excellent corrosion resistance, low density and good mechanical properties. However, at moderate and high temperatures (50-250\u0026deg;C) these alloys are vulnerable to sensitization, which is precipitation of \u0026beta; phase (Al3Mg2) preferentially on the grain boundaries (GBs). This \u0026beta; phase is more electrochemically active compared to the rest of the Al matrix. As a result, the \u0026beta; phase is preferentially dissolved when the samples are exposed to corrosive environments, making them susceptible to intergranular corrosion and environmentally induced stress corrosion cracking. The primary objective of this research is to characterize and understand the most influential microstructural parameters that dictate \u0026beta; phase precipitation and thus, local intergranular corrosion (IGC) susceptibility of aluminum 5456 in corrosive environments.\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003EMy objective is to understand the influence of microstructural features on \u0026beta; phase precipitation, with a focus on extrinsic characteristics like dislocation density and the intrinsic characteristics, misorientation angle and GB plane. For dislocation density study, AA5456 alloy microstructure is characterized using electron backscatter diffraction (EBSD) which facilitates the measurement of the geometrically necessary dislocation density, GB misorientation angle, and various other microstructural features.\u0026nbsp; After characterization, the sample is subjected to in-situ optical microscopy corrosion experiments, where the sample is immersed in 1% phosphoric acid while the corrosion events occurring on the surface are recorded. These videos are then analyzed to track the progress of IGC, and the corresponding corrosion maps are extracted from them. Image analysis tools and direct comparisons are used to obtain spatial correlations from corrosion maps and maps of microstructural features. To obtain information on GB plane, another microstructural feature of interest, a serial sectioning method will be used. This method consists of a series of mechanical polishing and EBSD mapping cycles to reconstruct a 3D microstructure from 2D microstructural data. This is facilitated by using fiducial markers on the surface and by manually aligning the 2D scans with the help of these markers. The grain boundary plane information will then be determined using an appropriate software. The influence of intrinsic and extrinsic characteristics of GBs on \u0026beta; phase precipitation will be analyzed using data analytics tools. Gaining a better understanding of the interplay of differing microstructural features on grain boundary precipitation of AA5456 alloy will open the door for microstructure sensitive design for enhanced corrosion resistance properties.\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"In-Situ Optical Microscopy Corrosion Experiments to Study the Influencing Microstructural Parameters on \u03b2 Precipitation in AA 5456"}],"uid":"27707","created_gmt":"2020-04-10 15:37:35","changed_gmt":"2020-04-21 18:04:42","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2020-04-23T11:00:00-04:00","event_time_end":"2020-04-23T13:00:00-04:00","event_time_end_last":"2020-04-23T13:00:00-04:00","gmt_time_start":"2020-04-23 15:00:00","gmt_time_end":"2020-04-23 17:00:00","gmt_time_end_last":"2020-04-23 17:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"102851","name":"Phd proposal"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}