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This work reports on optimizing the Indirect Indentation Method for measuring the elastic properties of brittle materials by indentation. The method employs a thin metallic film that protects the brittle material by absorbing the inelastic damage causes by the penetrating indenter. It applies hyperbolic identities to the Zhou-Prorok Model for thin film indentation that approach an asymptote as the indenter advances toward the film/substrate interface. The slope of this asymptote has been shown to be directly related to the elastic modulus of the brittle material being tested. A parameter study was conducted and revealed that the method can be optimized when the film Poisson's ratio is lower than the brittle material tested. This more directly transfers the indenter load to the substrate, enabling it to participate in the composite elastic response earlier in the indentation process. The result is an expanded range of fit of the experimental data to the models linear asymptote, providing more accurate elastic property measurements. Chromium was identified as an ideal film material due to its low Poisson's ratio, ductility and ability to be deposited onto most ceramics with a strong interface. The improvement was demonstrated on 5 brittle materials with a wide variety of elastic properties; SiC, Al 2 O 3 , MgO, SiO 2 , CaCO 3. [ABSTRACT FROM AUTHOR]

Niobium-doped titania (TNO) film can be used as a transparent conductive oxide (TCO) film due to its excellent conductivity and visible transparency. The performances of TNO sputtering targets are thus critical issues in optimizing sputtered films. This study clarifies the influences of inert and reducing atmospheres on the microstructure, densification, crystal structure, and electrical properties of TNO sputtering targets. The results indicate that a sintering atmosphere of 90% Ar–10% H 2 can result in a lower sintered density, larger grain size, and lower resistivity than can an atmosphere of Ar, followed by one of air. Sintering in 90% Ar–10% H 2 or Ar obviously decreases the resistivity of TiO 2 , from >10 8 Ω cm to <10 −1 Ω cm, and the TNO target, from >10 1 Ω cm to <10 −1 Ω cm. The resistivity of TNO target sintered at 1200 °C in 90% Ar–10% H 2 is as low as 1.8×10 −2 Ω cm. [ABSTRACT FROM AUTHOR]