25 research outputs found

    A preliminary characterization of the tensile and fatigue behavior of tungsten-fiber/Waspaloy-matrix composite

    Get PDF
    A microstructural study and a preliminary characterization of the room temperature tensile and fatigue behavior of a continuous, tungsten fiber, Waspaloy-matrix composite was conducted. A heat treatment was chosen that would allow visibility of planar slip if it occurred during deformation, but would not allow growth of the reaction zone. Tensile and fatigue tests showed that the failed specimens contained transverse cracks in the fibers. The cracks that occurred in the tensile specimen were observed at the fracture surface and up to approximately 4.0 mm below the fracture surface. The crack spacing remained constant along the entire length of the cracked fibers. Conversely, the cracks that occurred in the fatigue specimen were only observed in the vicinity of the fracture surface. In instances where two fiber cracks occurred in the same plane, the matrix often necked between the two cracked fibers. Large groups of slip bands were generated in the matrix near the fiber cracks. Slip bands in the matrix of the tensile specimen were also observed in areas where there were no fiber cracks, at distances greater than 4 mm from the fracture surface. This suggests that the matrix plastically flows before fiber cracking occurs

    Bending Properties of Nickel Electrodes for Nickel-Hydrogen Batteries

    Get PDF
    Recent changes in manufacturing have resulted in nickel-hydrogen batteries that fail prematurely by electrical shorting, This failure is believed to be a result of a blistering problem in the nickel electrodes. In this study the bending properties of nickel electrodes are investigated in an attempt to correlate the bending properties of the electrode with its propensity to blister. Nickel electrodes from three different batches of material were tested in both the as-received and impregnated forms. The effects of specimen curvature and position within the electrode on the bending strength were studied, and within-electrode and batch-to-batch variations were addressed. Two color-imaging techniques were employed to differentiate between the phases within the electrodes. These techniques aided in distinguishing the relative amounts of nickel hyroxide surface loading on each electrode, thereby relating surface loading to bend strength. Bend strength was found to increase with the amount of surface loading

    ‘Salesmen of the Will to Want’: Advertising and its Critics in Britain 1951–1967

    No full text
    Through the 1950s and 1960s, a sustained public debate about advertising's economic and social role occurred. This was a debate dominated by the critics of advertising. Across a swathe of educated opinion, an almost obsessive fascination with and scrutiny of advertising flourished. The arrival of commercial television in 1955 and with it television advertising stirred new popular, as well as elite, anxieties. For its critics amongst the viewing public, 'commercials' spoilt their enjoyment of television: there were too many adverts, they interrupted programmes and they were repetitive. These negative feelings towards their practice were the cause of considerable concern for the representatives of the advertising industry. They had good grounds to be concerned. In a period in which advertising was subject to criticism from both an increasingly influential consumer's movement and with politicians prepared to use the law to tax and regulate commercial practices, the representatives of advertising saw themselves in a constant struggle to resist and limit the effects of government intervention in the operation of their business. How they did this and the nature of both the charges made against them and their defence of advertising form the focus of this article. © 2010 Taylor & Francis

    Towards an Advanced Linear International Collider

    No full text
    This document provides detailed information on the status of Advanced and Novel Accelerators techniques and describes the steps that need to be envisaged for their implementation in future accelerators, in particular for high energy physics applications. It complements the overview prepared for the update of the European Strategy for particle physics, and provides a detailed description of the field. The scientific priorities of the community are described for each technique of acceleration able to achieve accelerating gradient in the GeV~range or above. ALEGRO working group leaders have coordinated the preparation of their working group contribution and contributed to editing the documents. The preparation of this document was coordinated by the Advanced LinEar collider study GROup, ALEGRO. The content was defined through discussions at the ALEGRO workshop in Oxford UK, March 2018, and an advanced draft was discussed during a one day meeting prior to the AAC workshop in Breckenridge, CO, USA, August 2018. This document was submitted as an addendum to the ALEGRO submission to the European Strategy for Particle Physics
    corecore