Attack of Scaling-Resistant Materials by Vanadium Pentoxide And Effect of Various Alloying Elements Thereon★

Abstract

Abstract Investigation into possibilities of developing metallic materials able to stand up under the attack by the combustion gases in crude-oil fired gas turbines is described. Preliminary comparative scaling tests were conducted on metallic copper, nickel, iron, and on chromium steels in pure oxygen, V2O5-saturated oxygen, and in oxygen coupled with intermittent immersion into molten V2O5. V, Mo, and W were found to be harmful elements. An explanation is given of action of V2O5. Other oxides and mixtures of oxides causing accelerated oxidation also are considered. An account is given of the development of a rapid test which would determine resistance to attack by V2O5. Test data are given on numerous steels and alloys known to be scaling resistant. Nature of V2O5 attack upon iron-base alloys is compared with that for nickel and Ni alloys. Numerical data are given on effect of Cr, Ni, and Si on scaling by V2O5. It is concluded that a metallurgical approach can partly solve the corrosion problem involved in V2O5 scaling. 3.5.9