2026-09-20T20:04:20Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/108085 2023-07-11 col_2142_5131 col_2142_13836 com_2142_5130 com_2142_13835 com_2142_234

Shoemaker, Daniel P Shoemaker, Daniel P Cahill, David G Perry, Nicola H Ertekin, Elif Murray, Shannon E. 2020-08-26T23:51:22Z 2020-08-26T23:51:22Z 2022-08-26T23:58:55Z 2020-02-07 2020-05 Improving the efficiency of synthesis methods in addition to establishing methods to produce novel materials or materials that are difficult to synthesize are driving factors in research for materials science. Flash sintering is both a method to densify ceramics within seconds and a method to rapidly synthesize materials. With the ability to use volatile precursors, avoid complete oxidation of elements, and locally cause transformations, flash sintering also provides a method of synthesizing compositions that would be difficult to produce conventionally. Although flash sintering is a technique with great potential to improve or expand upon current synthesis methods, the mechanisms have not been fully established. A variety of facets of flash sintering are presented in this thesis, all with the goal of understanding the mechanism of flash sintering so that it can be tailored and utilized for synthesis. By comparing two systems that are reduced during flash sintering, one with large contact resistance and the other with little contact resistance, the ability to utilize contact resistance for local heating to cause a phase transformation is shown. A method of predicting when a phase transformation will form will be discussed in addition to how kinetics and activation energy affect this prediction. An approach to using in situ Raman spectroscopy as a quantitative method to monitor defects during flash sintering is described. The effects of green body resistance and selected flash parameters on the flash temperature and the resulting phases are shown. By studying reduction reactions as model systems and utilizing in situ Raman to monitor defects and phases, we can gain further understanding of the mechanisms of flash sintering for its application as a versatile synthesis technique. Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2022-05-01 The student, Shannon Murray, accepted the attached license on 2020-02-06 at 11:42. The student, Shannon Murray, submitted this Dissertation for approval on 2020-02-06 at 12:19. This Dissertation was approved for publication on 2020-02-07 at 16:56. DSpace SAF Submission Ingestion Package generated from Vireo submission #14870 on 2020-08-25 at 17:26:32 Made available in DSpace on 2020-08-26T23:51:22Z (GMT). No. of bitstreams: 4 MURRAY-DISSERTATION-2020.pdf: 17197563 bytes, checksum: 5a5930878ba465b1d74d1172005fd9ac (MD5) Murray-thesis.zip: 31138398 bytes, checksum: 3486973c2b85ffff8269557422b51cfb (MD5) LICENSE.txt: 4211 bytes, checksum: 907d1ba2395bdd91acec35d9ac0d925b (MD5) Wiley copyright Mn2O3 paper.pdf: 819119 bytes, checksum: 2f8a4cf736a95798bd5ffdf8958788d6 (MD5) Previous issue date: 2020-02-07 Embargo set by: Seth Robbins for item 115694 Lift date: 2022-08-26T23:51:32Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115694 Lift date: 2022-08-26T23:54:40Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115694 Lift date: 2022-08-26T23:55:59Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115694 Lift date: 2022-08-26T23:57:28Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 115694 Lift date: 2022-08-26T23:58:55Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only application/pdf http://hdl.handle.net/2142/108085 en Copyright 2020 Shannon Murray Reactive Flash Sintering Raman Spectroscopy Understanding phase transformations during flash sintering text Thesis Materials Science & Engineerng Materials Science & Engr University of Illinois at Urbana-Champaign Dissertation Ph.D.