The aim of this paper is to create a research methodology that allows a quick analysis of the structural state of high alloy austenitic steels using non-destructive ultrasonic tests, in contrast to destructive standard methods. Electromagnetic acoustic transducers (EMAT) are used to generate and receive the ultrasonic wave and detect the microstructural changes caused by sample sensitization in elevated temperature, even after 0.5 h in high temperature exposition. Different acoustic response for reference sample and sensitized samples were recorded. In this work, changes in share wave amplitude were measured.
The paper presents the research results of the solenoid housing made of the Zn4Al1Cu alloy that was destroyed as a result of corrosion.
Surface of the tested part showed macroscopically the features typical for white corrosion, and the resulting corrosion changes led to a
disturbance of the alloy cohesion. The research performed have shown that the tested solenoid valve has intergranular corrosion as a
reaction of the environment containing road salt. The corrosion was initiated in the areas of the alfa phase existence appearing in the
eutectic areas which propagated over dendritic areas of the alloy. Initiation of the corrosion followed as a result of the galvanic effect of
the alfa phase reach in aluminium showing higher electrochemical potential, in contact with the eta phase reach in zinc. The impact of the
phase reach in lead present in the microstructure on the corrosion processes run was not found.