FATIGUE DAMAGE IN WOVEN CARBON FABRIC/EPOXY LAMINATES AT NON-AMBIENT TEMPERATURES

The mechanisms involved in initiation and development of non-ambient temperature fatigue damage in Plain Weave-Woven Carbon fabric/epoxy Composite laminates is explored. Laminates obtained from prepreg woven carbon fabric layers were subjected to tension-tension cyclic loading at –20oC, 0oC, 24oC 100oC and 150oC. Two different stacking sequences, a unidirectional [0]8, and an angle plied [0,0,45,-45]s sequence were studied. Optical microscopy, enhanced-dye penetrant X-ray radiography, and scanning electron fractography were employed to examine the fatigue damage mechanisms operative at various temperatures. Temperature was found to have a significant effect on the fiber/matrix bonding and interply delamination characteristics of these woven carbon fabric/epoxy laminates

Skeletal muscle contraction. The thorough definition of the contractile event requires both load acceleration and load mass to be known

<p>Abstract</p> <p>Background</p> <p>The scope of this work is to show that the correct and complete definition of the system of muscle contraction requires the knowledge of both the mass and the acceleration of the load.</p> <p>Results</p> <p>The aim is achieved by making use of a model of muscle contraction that operates into two phases. The first phase considers the effects of the power stroke in the absence of any hindrance. In the second phase viscous hindrance is introduced to match the experimental speed and yield of the contraction. It is shown that, at constant force of the load, changing load acceleration changes the time course of the pre-steady state of myofibril contraction. The decrease of the acceleration of the load from 9.8 m.s^-2to 1 m.s^-2increases the time length of the pre-steady state of the contraction from a few microseconds to many hundreds of microseconds and decreases the stiffness of the active fibre.</p> <p>Conclusions</p> <p>We urge that in the study of muscle contraction both the mass and the acceleration of the load are specified.</p

Effect of Sandblasting on Tensile Properties, Hardness and Fracture Resistance of a Line Pipe Steel Used in Algeria for Oil Transport

International audienc

Reduction of hydrogen embrittlement of API 5l X65 steel pipe using a green inhibitor

International audienc