The transport of oxygen to the advancing internal oxide front during internal oxidation of nickel-base alloys at high temperature

摘要: Abstract For Ni-Al alloys (containing 0.5 to 4 wt% Al), the depths of penetration internal oxide precipitates on exposure Ni/NiO packs at 800–1100°C are relatively independent alloy composition. However, for Ni-Cr 1 5 Cr), decrease with increasing chromium concentration, although generally a lesser extent than expected from classical theory. At all temperatures, two systems approximately coincide lowest aluminium and concentrations. The results can be related sizes, shapes distributions accounted in terms enhanced diffusion oxygen along incoherent interface between matrix. In particular, system continuous rods which extend surface front while those discrete, often spherical, particles. model accounts observations if ratio coefficient that through bulk nickel lattice is 1.5×10 800°C, decreasing temperature 6×10 3 1100°C.