Ducropur, Ducrolloy - New chromium materials

H.-P. Martinz; W. Köck; T. Sakaki

doi:doi:10.1051/jp4:1993919

Proceedings of the 3rd International Symposium on High Temperature Corrosion and Protection of Materials
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
DOI: 10.1051/jp4:1993919

Ducropur, Ducrolloy - New chromium materials

H.-P. Martinz¹, W. Köck¹ and T. Sakaki²

¹ Metallwerk Plansee, Reutte, Austria
² Tosoh Corp., Tokyo, Japan

Abstract
"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.