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Freestanding FeCrAl-Y2O3 amorphous/crystalline composite coating with a thickness of about 200μm has been produced from electron-beam physical vapor deposition of FeCrAl and yttria materials with a substrate temperature of 500 oC around. The microstructure was composed of columnar grains near the substrate side and an amorphous top layer. Local crystallization occurred during room temperature preservation. It is inferred that the crystallization activation energy of the material is very low.

As a rapid deposition method, Electron Beam Physical Vapor Deposition (EBPVD) permits the fast fabrication of self-standing thick coatings with thickness in the range from several micrometers to hundreds of micrometers. In this paper, we present a new way to fabricate ferritic ODS alloy foil. By this method, 1.2 wt.% of yttria was successfully added to the ferritic base material. The base alloys are mainly composed of bcc structured Fe (Cr,Al) solid solution. The steady state creep rate of ferritic ODS is almost two magnitudes lower than that of FeCrAl alloy. Further thermo-mechanical treatment is expected to improve strength and ductility of both ODS and non-ODS material.

Large scale Ni-based alloy sheets are prepared by electron beam physical vapor deposition with and without tungsten added into melting pools respectively. Addition W increased vapor rate and decreased compositional transformation during deposition. Chemical constitution of the sheet prepared through tungsten is more similar to that of the ingot. Microstructure of two alloy sheets is observed by scanning electron microscope (SEM) and atom force microscope (AFM). The results show that both of the sheets consist of columnar grains, whose major axes are almost parallel to the normal direction of the sheet. However, the average diameter of grains of the sheet through tungsten is larger than that of the sheet not through tungsten in minor axis direction. Mechanical properties and failure mechanisms of both sheets are studied. Tensile tests are conducted on a number of specimens. Strength, strain-to-failure are estimated under loading condition. The results show that the sheet prepared by EB-PVD through tungsten has a superior strength and an elongation percentage than that of the one prepared without tungsten.

Large-sized Fe-based ODS (Oxide Dispersive Strengthen) high-temperature alloy sheets were successfully synthesized by EBPVD (Electron Beam Physical Vapor Deposition) technique. The sheets were about 120μm thick, and having a diameter of 1000mm, whose surface roughness was less than 1μm (Ra