Skip to Main Content
 

Global Search Box

 
 
 

ETD Abstract Container

Abstract Header

STUDY OF ANODIC OXIDE FILMS ON TITANIUM AND TITANIUM-ZIRCONIUM ALLOYS AND THEIR POTENTIAL FOR CAPACITIVE ENERGY STORAGE

Chung, Min Kyong
http://rave.ohiolink.edu/etdc/view?acc_num=case1441383577

Abstract Details

2016, Doctor of Philosophy, Case Western Reserve University, Materials Science and Engineering.
Study of Anodic Oxide Films on Titanium and Titanium-Zirconium Alloys and their Potential for Capacitive Energy Storage Abstract by MIN-KYONG CHUNG Anodic oxide films were formed on titanium and titanium-zirconium alloys. They were studied for their ability to serve as dielectrics for storage of electrical energy and for their utility as anodes of electrolytic capacitors. The work comprised a study of the development of structure and electrochemical properties of TiO2 and of mixed TiO2-ZrO2 oxide films during their short-time anodic formation and during long-time repair-anodization in oxidizing electrolyte. The TiO2 anodic films evolved from an initially homogeneous amorphous state by nucleation of nanometer-sized grains and by additional recrystallization into films with islands of nm-grains and eventually with `anatase’-phase oxide nodules. They became embedded in the inner parts of the film, forming a stratified oxide layer and eventually replaced and overgrew most of the original anodic film. During this development the electrochemical parameters and the oxide-dielectrics’ property changes were recorded in-situ and interpreted by electrochemical impedance spectroscopy (EIS) and by equivalent circuit (EC) modeling. The permittivity of the films increased as a result of the recrystallization. However, their leakage currents increased also and diminished their useful electric field strength. Mixed TiO2-ZrO2 films were formed by anodizing Ti-Zr alloy. They developed in similar fashion as the TiO2 films, except they remained relatively homogenous during long-time anodization because of their resistance to recrystallization. They maintained a lower leakage current and were better suited as a capacitor dielectric. Another objective was the development of a process to synthesize homogeneous anodes of Ti-Zr anode alloy with high surface enhancement. The process is based on magnesiothermic reduction of titanium and/or zirconium halides and the sinter-bonding of the so-formed alloy particles. It formed nanocomposites of interpenetrating Ti-Zr alloy and magnesium-halide salts. After removal of the salts by distillation open-porous alloy specimens were obtained that could be anodized to convert their surface into a continuous (Ti-Zr)O2 oxide film. By variation of the processing times and temperatures the process rates of reduction and sintering could be controlled. Ti-Zr alloy sponge samples were produced with nm-sized branch and pores. They were suited as electrolytic capacitor anodes.
Gerhard Welsch, Dr. (Advisor)
Matthew Willard, Dr. (Committee Member)
Sehirlioglu Alp, Dr. (Committee Member)
Merat Francis, Dr. (Committee Member)
194 p.
Energy; Engineering; Materials Science
capacitive energy storage, anodic titanium oxide film, capacitance, electrochemical impedance spectroscopy, Ti-Zr alloy, spongy structure

Recommended Citations

Citations

  • Chung, M. K. (2016). STUDY OF ANODIC OXIDE FILMS ON TITANIUM AND TITANIUM-ZIRCONIUM ALLOYS AND THEIR POTENTIAL FOR CAPACITIVE ENERGY STORAGE [Doctoral dissertation, Case Western Reserve University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=case1441383577

    APA Style (7th edition)

  • Chung, Min Kyong. STUDY OF ANODIC OXIDE FILMS ON TITANIUM AND TITANIUM-ZIRCONIUM ALLOYS AND THEIR POTENTIAL FOR CAPACITIVE ENERGY STORAGE . 2016. Case Western Reserve University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=case1441383577.

    MLA Style (8th edition)

  • Chung, Min Kyong. "STUDY OF ANODIC OXIDE FILMS ON TITANIUM AND TITANIUM-ZIRCONIUM ALLOYS AND THEIR POTENTIAL FOR CAPACITIVE ENERGY STORAGE ." Doctoral dissertation, Case Western Reserve University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1441383577

    Chicago Manual of Style (17th edition)

case1441383577
1,706
© 2015, all rights reserved.
This open access ETD is published by Case Western Reserve University School of Graduate Studies and OhioLINK.
Release 3.2.12