Chapter 7 Alloy Oxidation III: Multiphase Scales

摘要: Publisher Summary Practical heat-resisting alloys have multiple components, nearly all of which are susceptible to oxidation in a wide range environments. When these exposed at high temperatures, an initial, transient period reaction alloy components oxidize, is followed by steady-state reaction. The rapid development corrosion-resistant, scale morphology the basis for design and selection, central concern this chapter. It predicts nature as function composition environmental variables. Of particular interest conditions leading protective, slow-growing oxide on surface. ability resist penetration gaseous impurities, such sulfur carbon obvious interest, also its block outward diffusion other components. prediction morphologies realistic goal single-oxidant environments, because oxidant activity must decrease monotonically from scale–gas interface interior. gradient provides driving force interfacial mass transfer. Discussions commenced with Wagner's analyses binary alloys. These distinguished classes relative affinities oxygen constituent metals. chapter focuses chromia alumina formation processes that can accompany them. A review examination effect ternary additions.