Structure and Properties of High-Strength Ti Grade 4 Prepared by Severe Plastic Deformation and Subsequent Heat Treatment

0524048 - ÚJF 2021 RIV CH eng J - Článek v odborném periodiku
Michalcová, A. - Vojtěch, D. - Vavřík, J. - Bartha, K. - Beran, Přemysl - Drahokoupil, Jan - Dzugan, J. - Palán, J. - Čížek, J. - Lejček, Pavel
Structure and Properties of High-Strength Ti Grade 4 Prepared by Severe Plastic Deformation and Subsequent Heat Treatment.
Materials. Roč. 13, č. 5 (2020), č. článku 1116. E-ISSN 1996-1944
Grant CEP: GA ČR GBP108/12/G043; GA MŠMT LM2015056; GA MŠMT(CZ) LM2015073; GA MŠMT LM2015087
Výzkumná infrastruktura: Reactors LVR-15 and LR-0 II - 90120
Institucionální podpora: RVO:68378271 ; RVO:61389005
Klíčová slova: PAS * TEM * Ti grade 4 * neutron diffraction
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.); Condensed matter physics (including formerly solid state physics, supercond.) (FZU-D)
Impakt faktor: 3.623, rok: 2020
Způsob publikování: Open access
https://doi.org/10.3390/ma13051116

Severe plastic deformation represented by three passes in Conform SPD and subsequent rotary swaging was applied on Ti grade 4. This process caused extreme strengthening of material, accompanied by reduction of ductility. Mechanical properties of such material were then tuned by a suitable heat treatment. Measurements of in situ electrical resistance, in situ XRD and hardness indicated the appropriate temperature to be 450 degrees C for the heat treatment required to obtain desired mechanical properties. The optimal duration of annealing was stated to be 3 h. As was verified by neutron diffraction, SEM and TEM microstructure observation, the material underwent recrystallization during this heat treatment. That was documented by changes of the grain shape and evaluation of crystallite size, as well as of the reduction of internal stresses. In annealed state, the yield stress and ultimate tensile stress decreased form 1205 to 871 MPa and 1224 to 950 MPa, respectively, while the ductility increased from 7.8% to 25.1%. This study also shows that mechanical properties of Ti grade 4 processed by continual industrially applicable process (Conform SPD) are comparable with those obtained by ECAP.
Trvalý link: http://hdl.handle.net/11104/0308360