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To characterise anomalies embedded in graphite fibre reinforced aluminium matrix composite, chirplet parameters of ultrasonic signals were obtained by chirplet signal decomposition method. It was confirmed that the parameters of decomposed chirplets can represent the characteristic of ultrasonic signals in time and frequency domains compared with conventional time and frequency analysis method. Chirplet parameters were used to identify three types of anomalies embedded in graphite fibre reinforced aluminium matrix composite. The variations of centre frequency and phase of three anomalies were interpreted by frequency dependent attenuation coefficient of composite and frequency dependent reflection coefficient of thin anomalies embedded in composite.

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.

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.