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Causes of failure of brass condenser tubes (CuZn28Sn1) in a thermal power plant in Serbia are analysed. Results of testing by Fourier transformed infrared spectroscopy (FTIR) have indicated the presence of ammonia and nitro- gen compounds on fracture surfaces and on the inner surface of the tubes. These compounds are specific agents that cause stress corrosion cracking (SCC) in brass. Analy- sis of fracture surfaces using scanning electron microscopy (SEM) has shown the brittle transgranular fracture due to the occurrence of SCC. The resistance of brass condenser tubes to other types of corrosion, such as erosion, general and selective corrosion (dezincification) is also considered. Some procedures are proposed to reduce the risk of SCC in the brass condenser tubes. Analizirani su uzroci pojave loma kondenzatorskih cevi od mesinga CuZn28Sn1 u jednoj termoelektrani u Srbiji. Rezultati ispitivanja metodom Furijeove transformisane infracrvene spektroskopije (FTIR) ukazuju na prisustvo amonijačnih i azotnih jedinjenja na površini loma i na unutrašnjoj površini cevi. Ta jedinjenja su specifični agensi za pojavu naponske korozije mesinga. Analiza površine loma primenom skening elektronske mikroskopije (SEM) pokazala je prisustvo krtog transkistalnog loma nastalog usled pojave naponske korozije. Razmatrana je otpornost cevi od mesinga CuZn28Sn1 prema drugim vidovima koro- zije, kao što su eroziona, opšta i selektivna korozija (decin- kacija). Predloženi su postupci za smanjenje rizika od pojave naponske korozije u kondenzatorskim cevima.

This is the memorial lecture devoted to Prof. Stojan Sedmak, the principle researcher of the USA-Yu project „Weldment Fracture Mechanics”, 1982-1990. Selected results of the project has been presented and analysed, as well as the huge impact of this project and Prof. Stojan Sedmak on the development of Fracture Mechanics and Structural Integrity in the whole region. All authors have participated in the project, directly or indirectly.