Bulletin AKI

Výzkumné články

Causes of reduced corrosion resistance of stainless steels and alloys

Bystrianský J. a spol.
2000, 44 (EN), 2–6

Citace (ACS): Bystrianský, J.; et al. Causes of reduced corrosion resistance of stainless steels and alloys. Koroze a ochrana materiálů 2000, 44 (EN), 2–6.

Citace (ISO): Bystrianský, J.; et al. Causes of reduced corrosion resistance of stainless steels and alloys. Koroze a ochrana materiálů 2000, vol. 44, no. EN, p. 2–6.

Corrosion resistance of stainless steels and alloys depends both on their basic chemical composition, i.e. the content of alloying elements, and on the state of surface. The decrease of resistance of stainless material surface layer can show negative effects even under quite mild corrosion conditions (atmosphere, neutral aqueous solutions etc.) - it means that surface or localized corrosion can appear. The negative change of surface quality of these materials, i.e. of corrosion resistance, can be caused by unsuitable influencing of chemical and physical state of the surface [I-41.
Výzkumné články

Is risk based inspection right for you

Vácha F.J.
2000, 44 (EN), 7–9

Citace (ACS): Vácha, F. Is risk based inspection right for you. Koroze a ochrana materiálů 2000, 44 (EN), 7–9.

Citace (ISO): Vácha, F. Is risk based inspection right for you. Koroze a ochrana materiálů 2000, vol. 44, no. EN, p. 7–9.

The main question about RBD or RBI is not whether to base decisions on risk assessment. Most of the important business decisions are almost always supported by either explicit or implicit risk vs. benefit consideration. The difficult part is to make the processes more effective, easy to apply and comparable.
Výzkumné články

Developement of corrosion protection and corrosion resistance of cars

Rendahl B.
2000, 44 (EN), 10–15

Citace (ACS): Rendahl, B. Developement of corrosion protection and corrosion resistance of cars. Koroze a ochrana materiálů 2000, 44 (EN), 10–15.

Citace (ISO): Rendahl, B. Developement of corrosion protection and corrosion resistance of cars. Koroze a ochrana materiálů 2000, vol. 44, no. EN, p. 10–15.

Several years ago, car manufacturers and suppliers introduced long-term guarantees against perforation corrosion. This is a positive development, but does this mean that the car owner doesn't have to worry about the risk of heavy corrosion on vehicles of recent models? Different factors will affect to what extent a car will corrode. One of the most important factors is the road environment. In the northern part of Europe where deicing salt is used frequently during the winter period the car corrosion can accelerate up to 10 times compared with areas not using deicing salt [I]. For these corrosive regions it is most important with good corrosion protection and high corrosion resistance of the car.
Výzkumné články

Problems of constructional materials resistance to aggresive environments with possibility of stress corrosion cracking

Horák Z.
2000, 44 (EN), 16–21

Citace (ACS): Horák, Z. Problems of constructional materials resistance to aggresive environments with possibility of stress corrosion cracking. Koroze a ochrana materiálů 2000, 44 (EN), 16–21.

Citace (ISO): Horák, Z. Problems of constructional materials resistance to aggresive environments with possibility of stress corrosion cracking. Koroze a ochrana materiálů 2000, vol. 44, no. EN, p. 16–21.

A transit system, represented mainly by the system of extremely high-pressure and high-pressure gas pipelines, includes besides main lines also converted gas lines. These gas lines have been often subjected to conversion from original transport of lighting gas. Expossure in lighting gas, i.e. in very aggressive environment characterized namely by a content of sulphane, represents a considerable danger for future operation of these gas lines. This is caused by the degradation due to corrosion processes that can consequently occur on the inside surface of tubes. Experiences obtained during providing rehabilitation on operating high-pressure or medium-pressure gas lines of the current distribution system have only confirmed these presumptions. Due to the superposition of the influence of corrosion processes and presure tests, the pipe line materials are destroyed very often.