Metallic glasses characterized

Metallic glasses are alloys that have been cooled so rapidly that no crystal structure has had time to develop, for example, Pd-Si, Pd-Ge, Fe-Ge (Metglas). These materials are characterized by the absence of sharp lines in their X-ray spectra. 

V-Ti-Ni alloys and Fe- /Co-Based metallic glasses have been evaluated with respect to hydrogen permeability for potential use in hydrogen purification membrane reactor application. Microstructural characterization of the V-Ti-Ni alloy using SEM has shown similar microstructural features to a previously evaluated Nb-Ti-Ni alloy namely, the occurrence of a primary phase surrounded by interdendritic eutectic. 

In this chapter, we define some important terms and parameters that are commonly used with fibers and fiber products such as yams, fabrics, etc., and then describe some general features of fibers and their products. These definitions, parameters, and features serve to characterize a variety of fibers and products made from them, excluding items such as fiber reinforced composites. These definitions and features are generally independent of fiber type, i.e. polymeric, metallic, glass or ceramic fibers. They depend on the geometry rather than any material characteristics. 

Pan, D., Inoue, A., Sakurai, T., and Chen, M. W. (2008) Experimental characterization of shear transformation zones for plastic flow of bulk metallic glasses, Proc. Natl. Acad. Sci., 105, 14769-14772. 

With few exceptions, the most abundant components of the archaeological record are inorganic solids, which typically include ceramics, lithics, metals, glass, and mineralized animal tissue (bone and teeth). Archaeologists, whose job is to describe and account for this record in terms of past events and processes, have long sought to develop and/or adapt techniques for characterizing such materials. 

Actually, minerals which are transparent transmit light much like glass. These minerals are essentially solids with ionic or covalent bond such as oxides, carbonates, silicates (e.g., calcite, quartz), or native element (e.g., diamond). Minerals which are translucent transmit light on thin edges or in thin section. By contrast, opaque minerals do not transmit light even in thin section and comprise solids with metallic or partially metallic bond characterized by a free electron cloud (i.e., Fermi gas) such as native element (e.g., Cu, Ag, Au), most iron and copper bearing sulfides (e.g., CuS, FeS ), and several transition metal oxides (e.g., Fe, ,. FeTiOj, FeCrp J. As a general rule, all minerals with a metalhc luster are commonly opaque. 

In the simple case of free-standing electrodeposits, or deposits that completely cover the substrate, the corrosion behavior may be characterized by the standard procedures described in Sections HI and IV of this manual. As with materials produced 1 other means, the corrosion performance of the deposit may be expected to be a sensitive function of the composition and microstructure, which are determined by the processing conditions. Interestingly, electrochemical deposition may be used to generate a variety of novel metastable materietls. The deposition of certain metallic glasses or supersaturated single-phase materials offers the promise of remarkable corrosion resistance. For example, electrodeposited Ni Cr P metallic glass has been shown to exhibit corrosion characteristics superior to Hastelloy C-276 (Fig. 1) [/]. The nature of the p>assive film formed on Ni-Cr-P metallic... 

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