Corrosion Behavior of Titanium Tubes

The paper deals with the presentation of results obtained from a research on titanium tubes. The tubes have been investigated after 10 years using into practice as parts of heater vessel. Outside of tubes contact with a gas mixture of steam and ammonia at temperature 97^oC. The study covers - visual and dimensional inspection, chemical composition, micristructure, tensile strength, elongation, hardness, compress deformation. The investigations include various areas of tubes with different service conditions as temperature, crrosion agent, mehanical stress. The results show that set chahges depend on the workinh conditions. Possibilities for tube damage are a result of possibilities of corrosion sttack. The corrosion attack changes the tube material microstructure. These alterations direct to the alteration of  mechanical properties. The tube life duration depends on the  degree of corrosion attack. The main problem contacts with the ifectdegree of base titanium matrix from the corrosion agent.