Abstract Scope |
Among the several potential candidates for a new generation of ultrahigh temperature structural materials, Mo-Si-B alloys have drawn much attention due to their high melting point and high temperature strength. In the Mo-Si-B system, nearly all the research has focused on the Mo-rich corner, especially the Moss+Mo5SiB2 (T2) + Mo3Si three phase region. Recently, a series of Mo-Si-B alloys was designed in the Moss+T2 (Mo5SiB2)+Mo2B three phase region to examine the effect of the lower Si solubility limit in the Moss phase on the microstructure, hardness and oxidation behavior. The results showed that Mo-Si-B alloys in the Moss+T2 (Mo5SiB2)+Mo2B three phase region have higher fracture toughness and same level oxidation resistance as the Moss+T2 + Mo3Si alloys In the present study, oxidation of Mo-Si-B alloys at different Al addition levels was examined at 1100, 1200, and 1300°C. Under both isothermal oxidation and cyclic exposure the oxidation resistance was enhanced considerably. |