High-temperature oxidation of heat-resistant alloys with small amounts of sulfur and reactive elements (Y, Hf) for 1800ks at 1373K

Abstract

High-temperature oxidation of heat-resistant alloys with small amounts of sulfur and reactive elements (Y, Hf) was studied for 1800ks in air at 1373K. The mass changes of the 2, 53, 104 and 171ppmS were 0.5-0.9×10^-2kg/m². On the other hand, the mass changes of the 5, 185, 491 and 1300ppmS were less than 0.2×10^-2kg/m² or negative values because of marked spalling of oxide scale on the alloys. Oxide on the 1300ppmS was convoluted, and those on the alloys with reactive elements were planar morphology. The formation of planar morphology on the oxide and that of stable reactive elements sulfide particles may lead to good oxide adherence.