Browsing by Subject "zdrowienie"

Now showing 1 - 3 of 3

Access status: Open Access ,
Badanie charakterystyk miedzi i aluminium po silnych odkształceniach plastycznych
(Data obrony: 2020-10-16) Malik, Radosław
Wydział Fizyki i Informatyki Stosowanej
Access status: Restricted ,
Metalografia ilościowa w ocenie mikrostruktury stopów tytanu
(Data obrony: 2020-01-24) Baran, Patryk
Wydział Inżynierii Metali i Informatyki Przemysłowej
Access status: Open Access ,
Naprężenia własne w materiałach polikrystalicznych oraz ich zmienność podczas obróbki termicznej
(Data obrony: 2012) Wawszczak, Roman
Wydział Fizyki i Informatyki Stosowanej
Structural defects and various kinds of residual stresses appearing in polycrystalline materials and their evolution during thermal treatment are discussed in the thesis. Moreover, two models of elastoplastic deformation were verified and applied for materials with various stacking fault energy. The measurements were conducted for the sets of metallic samples with the high and low stacking fault energy, i.e. ferritic steel and copper, and austenitic steel and brass, respectively. The first order and second order incompatibility residual stresses were determined from experimental peak positions using multireflection $\sin^{2} \psi$ method. In this method the diffraction elastic constants calculated for textured material were applied. The models of elastoplastic deformation were used for interpretation of the experimental data. For the first time this methodology was applied for the material thermally treated after the initial deformation. Comparison of the residual stress (determined using the $\sin^{2} \psi$ method) with diffraction peak profile, microhardness evolution and calorimetric measurements shows that the changes of stress state inform us in advance about beginning of recovery and recrystallisation processes appearing in the annealed material. It was also found that the presence of numerous stacking faults delays the recovery process, while the precipitation and dissolution of carbides influences recrystallisation. Finally, it was proved that relaxation of the second order stresses during sample annealing occurs independently on the grain orientation.