Microstructure and mechanical properties of ultra-fine grained titanium alloys
| Thesis title in Czech: | Mikrostruktura a mechanické vlastnosti ultrajemnozrnných slitin titanu |
|---|---|
| Thesis title in English: | Microstructure and mechanical properties of ultra-fine grained titanium alloys |
| Key words: | ultrajemnozrnný materiál, slitiny titanu, mikrostruktura, mikrotvrdost, difrakce zpětně odražených elektronů, struktura defektů, fázové transformace |
| English key words: | ultra-fine grained materials, Ti alloys, microstructure, microhardness, electron back-scatter diffraction, defect structure, phase transformations |
| Academic year of topic announcement: | 2016/2017 |
| Thesis type: | rigorosum thesis |
| Thesis language: | angličtina |
| Department: | Department of Condensed Matter Physics (32-KFKL) |
| Supervisor: | doc. PhDr. RNDr. Josef Stráský, Ph.D. |
| Author: | hidden - assigned and confirmed by the Study Dept. |
| Date of registration: | 11.04.2017 |
| Date of assignment: | 11.04.2017 |
| Confirmed by Study dept. on: | 11.04.2017 |
| Date and time of defence: | 25.05.2017 00:00 |
| Date of electronic submission: | 11.04.2017 |
| Date of submission of printed version: | 11.04.2017 |
| Date of proceeded defence: | 25.05.2017 |
| Guidelines |
| 1) Student will compose literature review covering ultra-fine grained materials, biomedical titanium alloys and metastable beta titanium alloys.
2) Student will measure microhardness of different alloys after high-pressure torsion. 3) Student will observe microstructure of studied materials using light microscopy and electron microscopy. 4) Student will participate on dislocation density measurements. 5) Student will use in-situ experimental techniques to determine thermally activated processes in studied materials. 6) Microhardness measurements and microstructure observation will be correlated with parameters of severe-plastic deformation processes. 7) Recovery, recrystallization and phase transformation processes will be identified and correlated to thermal treatment. 8) Achieved results will be summarized in diploma thesis. |
| References |
| G. Lutjering, J.C. Williams; Titanium; Springer; 2007
A.P. Zhilayev, T.G. Langdon; Using high-pressure torsion for metal processing: Fundamentals and applications; Prog Mat Sci 53; 2008 O. Srba; Komplexní studium jemnozrnných polykrystalů Cu a slitiny CuZr připravených metodami equal channel angular pressing a high pressure torsion; disertační práce; 2011 R. Z. Valiev, I.P. Semenova, E. Jakushina, V.V. Latysh, H. Rack, T.C. Lowe, J. Petruželka, L. Dluhoš, D. Hrušák, J. Sochová; Nanostructured SPD Processed Titanium for Medical Implants, Mat Sci Forum Vols. 584-586; 2008 M. Janeček, J. Stráský, J Čížek, P. Harcuba, K. Václavová, V.V. Polyakova, I.P. Semenova; Mechanical properties and dislocation structure evolution in Ti6Al7Nb alloy processed by high pressure torsion, Met Mat Trans, April 2013 L.F. Zeipper, M.J. Zehetbauer, Ch. Hozleitner; Defect based micromechincal modelling and simulation of nanoSPD CP-Ti in post-deformation; Mat Sci Eng A 410-411, 2008 J. Čížek, M. Janeček, O. Srba, R. Kužel, Z. Barnovská, I. Procházka, S. Dobatkin; Evolution of defects in copper deformed by high-pressure torsion, Acta Mat 59, 2011 |
| Preliminary scope of work |
| The advantages of ultra-fine grained microstructure on mechanical properties have been studied for last two decades. However, production of ultra-fine grained (UFG) titanium and especially UFG titanium alloys has been made possible only in last few years. Experimental data describing properties of these materials are scarce and relations between material preparation, microstructure and mechanical properties are unrevealed. Simultaneously, there is increased interest in metastable beta titanium alloys that provide unique properties thanks to extreme hardening capabilities via series of phase transformations. The effect of ultra-fine grained microstructure on these phase transformations is unknown.
The diploma thesis aims on experimental characterization of UFG titanium alloys employing wide spectrum of experimental techniques. Furthermore, microstructure and defect structure evolution at elevated temperatures will be studied by in-situ and ex-situ methods. |