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 °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.

COMTES FHT Department of Mechanical Testing and Thermophysical Measurement Průmyslová 995 334 41 Dobřany Czech Republic

Department of Low‑Temperature Physics Faculty of Mathematics and Physics Charles University 5 Holešovičkách 2 CZ‑180 00 Prague 8 Czech Republic

Department of Metals and Corrosion Engineering University of Chemistry and Technology Prague Technická 5 166 28 Prague 6 Czech Republic

Department of Physics of Materials Charles University Ke Karlovu 5 121 16 Prague Czech Republic

European Spallation Source ERIC 222 70 Lund Sweden

Institute of Physics Academy of Sciences of the Czech Republic Na Slovance 2 182 21 Prague 8 Czech Republic

Nuclear Physics Institute ASCR in Řež Husinec‑Řež 130 250 68 Řež Czech Republic

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