![]() ![]() It is based on the simple idea of holding a tensile specimen between a pair of sliders with chamfered faces which are impacted upon by a wedge of matching semi-angles fired from a gas gun at high velocity, thereby subjecting the specimen to high speed uniaxial tension simultaneously from both ends (Sturges and Cole, 2001). The high strain rate tests were performed on the so-called ‘flying wedge’ dynamic tensile testing machine, Figure 3, which is capable of imparting simultaneous symmetrical loading at both ends of a tensile specimen over a wide range of loading speeds. This assumption was reasonable because the specimens showed no sign of incipient necking up until fracture. This change in gauge length and the corresponding load were then used to plot the true stress-true strain curve of the UHMWPE making the usual assumption of constant volume during plastic deformation. From these measurements, the change in gauge length of the specimen was obtained at each time increment using the Dartec analysis software. The load was read directly from the load digital display associated with the machine and the elongation of the axisymmetric specimen was measured using the stationary laser extensometer (Elsayed, 2000). The load and the corresponding elongation were recorded simultaneously at certain increments of cross-head displacement. quasi-static tests were conducted on a Dartec standard servo-hydraulic machine equipped with a laser extensometer, Figure 2. The dynamic tests (300–1000 s − 1 ) were conducted using a unique impact tensile test facility known as the ‘flying wedge’, Figure 3, which is capable of applying strain rates in the range 10 2 up to 10 4 s − 1 (Sturges and Cole. The quasi-static tests (0.005–0.05 s − 1 ) were carried out using a Dartec servo-hydraulic universal testing machine (Elsayed, 2000), Figure 2. The strain rate was varied by carrying out tensile tests at both quasi-static and dynamic rates, ranging from 0.005 up to 1000 s − 1. To obtain a range of stress triaxiality factor (defined as the ratio of the mean stress σ m to the von Mises effective stress σ e ), notches of different notch profile radius (4, 2, 1, and 0.5 mm) were machined in the plain cylindrical tensile specimens as shown in Figure 1b. 0 × 10 6 g mol − 1 and 936 kg m − 3, respectively (Kurtz et al., 1998). The reported average molecular weight and density for the UHMWPE used in this study are 2.0 to 4. The polymer sheet was compression molded by Poly Hi Solidur Meditech (Germany) from UHMWPE powder provided by Hoechst AG (Germany). specimens were machined from rectangular compression molded sheet of UHMWPE type GUR1120 to give a cylindrical cross-section of 3 mm diameter and 15 mm gauge length as shown in Figure 1a. Tobias, ambassador and former chief executive officer of Eli Lilly and Company Steinbrenner III, principal owner, New York Yankees Peavey, senior vice president for development and college relations, Wofford College, and executive director emeritus, NCAA Foundation Malloy, president emeritus, University of Notre Dame Lupberger, president, Nesher Investments, LLC Morris, executive director, United Nations World Food Program Stevie Eller and Karl Eller, chairman and chief executive officer, The Eller Company.Thomas Curley, president and chief executive officer, The Associated Press. ![]() Richard Cheney, Vice President of the United States of America.The award is given by the NCAA Leadership Advisory Board of Directors and there have been ten recipients: Ironically, the flying wedge formation was outlawed in college football in 1894 because it was highly dangerous. There is a life-size sculpture of the flying wedge in the NCAA Hall of Champions in Indianapolis and a reproduction is awarded as The Flying Wedge Award. The flying wedge was used in the early days of American football and became a symbol of the origin of the NCAA in 1906. It is awarded to an individual who exemplifies outstanding leadership and service to the NCAA. The Flying Wedge Award is one of the NCAA’s highest honors. JSTOR ( February 2009) ( Learn how and when to remove this template message).Please improve this by adding secondary or tertiary sources.įind sources: "The Flying Wedge Award" – news This article relies too much on references to primary sources. ![]()
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