Acoustic emission behavior at rolled metals during mechanical tests

V zaključnem delu je predstavljena neporušna metoda preizkušanja valjane pločevine z akustično emisijo. Postopek valjanja pločevine vpliva na usmerjenost mikrostrukture in posledično povzroča anizotropne mehanske lastnosti pločevine. Usmerjenost strukture je pomemben dejavnik pri mehanskih preizkusih, kar se odraža tudi na zaznanih signalih akustične emisije med obremenjevanjem vzorcev pločevine. Opisan je vpliv načina in smeri valjanja kovin na zaznano akustično emisijo vzorcev pri nateznih in upogibnih preizkusih. Predstavljen je vpliv nekovinskih vključkov na nastanek razpok in njihov vpliv na zaznano akustično emisijo v jeklih A533B tekom nateznih in upogibnih preizkusov. Opisan je vpliv valjanja na mehansko anizotropijo aluminijeve zlitine PA11 in α-medenine CuZn30 in njen vpliv na zaznane signale akustične emisije med nateznim preizkusom. Podobno je opisan vpliv vročega valjanja in popuščanja zlitine magnezija AZ31 na zaznano akustično emisijo med nateznim preizkusom.This final thesis presents testing of rolled sheet metal with acoustic emission is presented. The rolling procedure of sheet metal affects the orientation of microstructure and, consequently, causes the anisotropic mechanical properties of the sheet metal. Orientation of structure is important factor in mechanical tests, which is also reflected on detected acoustic emission signals during loading of sheet metal samples. The influence of the method and direction of rolling on the detected acoustic emission of samples in tensile and bending tests is described. The influence of the non-metallic inclusions on the formation of cracks and their influence on the perceived acoustic emission in A533B steels during tensile and bending tests is presented. The influence of rolling on the mechanical anisotropy of the aluminium alloy PA11 and the α-brass CuZn30 is described and its effect on the detected acoustic emission signals during tensile tests. Similarly the effect of the hot rolling and tempering of the AZ31 magnesium alloys on the detected acoustic emission during tensile tests is described