Uniaxial direction

It should be considered that in the case of plotting 1 = a/ X — X 2) against inverse extension ratio (X 1), the nominal stress a is defined as the force divided by the undeformed cross-sectional area of the sample and X is the extension ratio, defined as the ratio of deformed to the undeformed length of the sample stretched in the uniaxial direction (as shown in Fig. 3). For PTFE powder, the intrinsic strain is deduced from (2) by defining X - 1 ... 

Figure 2 is a comparison of the results obtained by our technique with the more conventional methodic that uses crossed polarizers with the uniaxial direction of the sample being at 45° to the axes of the polarizers. The intensity transmitted in this case is given by... 

In a controlled strain rate type of loading, used in uniaxial direct tensile tests, a controlled rate displacement is applied to the specimen in direct tension to provide a constant strain rate. 

A cone can be considered as a deformation of a cylinder, in which the poles of the uniaxial direction are no longer equivalent. The symmetry group is reduced accordingly to Coov, where only the vertical symmetry planes remain. Conical symmetry is exemplified by hetero-nuclear diatomic molecules, but it is also the symmetry of a polar vector, such as a translation in a given direction, or a polarized medium or an electric held, etc. Conical molecules have C v symmetries, as was the case for the ammonia model. Again, the smallest trivial member of this series is Civ, which is fully anisotropic. This is the point group of the water molecule. 

In this section, we start by considering the simplest case of continuous, uniaxially directed fibres loaded precisely in parallel or transversely to the fibre direction. Afterwards, we will discuss the case of arbitrary load orientation. 

When an external magnetic field is applied along the uniaxial direction, the magnetic energy is given by (0) = KV sin 0 - cos 6 [Eq. 

Another classification of composite materials is based on the morphology of the reinforcement introduced into the matrix. The composites therefore could be categorised into two main groups continuous reinforced system and discontinuous reinforced system. In the former, the matrix contains continuous fibres or filaments, which typically distribute in a uniaxial direction and enhance the strength and creep resistance of the matrix. In the latter, the matrix contains particulates, whiskers or chopped fibres, which distribute in the matrix uniformly in random orientations. Moderate toughening and reasonable levels of strengthening can be achieved. 

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