Naslov
The characterization of damages of the tubes made from stainless steel

Autori
Novosel – Radović, Vjera ; Radović, Nikol ; Iharoš, Ana ; Belić, †Anica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstract / Cetina, Mario ; Popović, Stanko ; Skoko, Željko ; Štefanić, Zoran ; Višnjevac, Aleksandar - Zagreb : Hrvatska kristalografska zajednica HAZU, 2011, 50-50

Skup
20th Croatian – Slovenian Crystallographic Meeting

Mjesto i datum
Krk, Hrvatska; Baška, Hrvatska, 15.06.2011. - 19.06.2011

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
damage; pipe system; austetnite steel; intercrystalline corrosion

Sažetak
Today stainless steel has wide application in every day practice. According to Pavlović1, this is due to its great mechanical and technological properties, a Satelja2 and Yap3 structure, chemical composition, protective surface layer, specific thickness, solidity, density and plasticity. The presence of any kind of phase transformation within a layer becomes one of the causes of breakage and intercrystalline corrosions on the boundary of extortion grains4. With the use of their expounding and Matula5, we are trying to interpret the appearance of the noted damages on the assembly line for the production of urea. In the investigation, samples were taken at the damaged places in the form of pieces of tube, sediment and/or sludge from the inner and outer surface of the tube. Powered samples taken were grounded and homogenized for five minutes in the Spex mixer mill. The prepared samples were examined directly using a Philips x - ray diffractometer and CoK radiation using a photographic technique and a scanning electron microscope and microanalysis. The concentration of chloride was determined using the x – ray emission spectrometry by the method of emission - transmission x – ray6. The obtained results were treated mathematically. The samples taken as pieces of tubes were cut into 10 x 10 mm plates and prepared by grinding and etching. The samples were examined using a light as well as a scanning electron microscope. The obtained results point to microstructural changes within the inner wall of the pipes and the appearance of intercrytalline corrosion as a result of the presence of aggressive phases of FeCl2 and FeCl3 and the phases of sediment of technological and feed water.

Izvorni jezik
Engleski

Znanstvena područja
Matematika, Kemija

POVEZANOST RADA