Actes du 3ème Colloque International sur la Corrosion et la Protection des Matériaux à Haute Température
J. Phys. IV France 03 (1993) C9-205-C9-213
Ducropur, Ducrolloy - New chromium materialsH.-P. Martinz1, W. Köck1 and T. Sakaki2
1 Metallwerk Plansee, Reutte, Austria
2 Tosoh Corp., Tokyo, Japan
"Ducropur" and "Ducrolloy" - powder metallurgically produced chromium and chromium base alloys represent a unique combination of different properties : high strength at elevated temperatures and good corrosion resistance to a large variety of chemicals as well as to hot gases. The present paper shows that Ducropur is one of the most resistant materials (better than LC-Ni) in hot caustic soda applications. Furthermore, it is shown that Ducrolloy Cr44Fe5AlO.3TiO.5Y2O3 is almost inert to boiling concentrated nitric acid. The corrosion rate is lower than that of most HNO3-resistant alloys cited in the literature. Finally, the hot air oxidation/nitridation behaviour of Ducropur can be improved by small additions of rare earth oxides and alloying with iron and aluminum. Alloys such as Cr1La2O3 and Cr44Fe5AlO.3TiO.5Y2O3 form tight protective layers and are promising materials for various hot gas applications.
© EDP Sciences 1993