Tensile properties of materials

The ASTM procedure describes procedures for determining tensile properties of materials in the form of standard dumbbell-shaped test specimens, with thickness between 1.0 mm (0.04 in.) and 14 mm (0.55 in.). The ASTM emphasizes, where directly comparable results are desired, that all samples should be of equal thickness. 

It is speculated that the water does not diffuse as easily into the polycarbonate as into the PTMEG urethane, making the polycarbonate more resistant to plasticization by water and subsequent hydrolysis. The tensile properties of the PTMEG polyurethane eventually returned to nearly the original tensile properties, if the material was allowed to dry at room temperature for 2 weeks. This observation lends credence to the idea that the PTMEG urethane was plasticized by water. 

Table 5 compares the tensile properties of Vectra A950 in the form of dispersed fibers and droplets in the matrix by injection molding, microfibril by extrusion and drawing [28], injection molded pure thick sample and pure thin sample, and the pure drawn strand [28]. As exhibited, our calculated fiber modulus with its average of 24 GPa is much higher than that of the thick and thin pure TLCP samples injection molded. It can be explained that in cases of pure TLCP samples the material may only be fibrillated in a very thin skin layer owing to the excellent flow behavior in comparison with that in the blends. However, this modulus value is lower than that of the extruded and drawn pure strand. This can be... 

Table 5 Tensile Properties of Vectra A950 as Fibers and as Pure Bulk Materials...

In the middle of the last century, the tensile properties of concrete were improved by the introduction of steel to reinforce the concrete. This practice has developed since then to such an extent that reinforced concrete is now one of the major structural materials used in construction. In general it has proved to be a good durable material with some of the structures erected at the turn of the century still providing satisfactory service in the late 1970s. 

The melting point of aluminium (660°C). The operating temperature usually reaches 750-850°C in pretreatment and 700°C in the bath, causing a loss in tensile properties of cold-drawn wire. On the other hand, if cold-worked material which is to be subsequently annealed is used in this process the annealing and coating operations may be combined, with obvious economic advantage. 

Standard Test Method for Tensile Properties of Plastics. D638-84. American Society for Testing and Materials Philadelphia, 1985, Vol 8.01, p 227. 

FFs that are parameterized for high-pressure conditions can still lead to behavior that differs from that observed in experiments. For instance, it is common practice to treat the interatomic interactions with Lennard-Jones (LJ) potentials. Although this method is convenient from a computational standpoint, it is known that LJ potentials do not reproduce experimentally observed behavior such as necking, where a material attempts to minimize surface area and will break under large tensile stresses. Many other examples exist where particular types of FFs cannot reproduce properties of materials, and once again, we emphasize that one should ensure that the FF used in the simulation is sufficiently accurate. 

Table r.6 Examples of tensile properties of various materials... 

ISO 1926 1979 Cellular plastics - Determination of tensile properties of rigid materials ISO 4587 2003 Adhesives - Determination of tensile lap-shear strength of rigid-to-rigid... 

LDPE/EVA blend was irradiated using gamma-irradiation and then expanded by heat as a foamed material. The EVA content in the blend was optimised to form a gel. The effects of atmospheres and of irradiation dose rate were studied. The ETIR spectra of the foam revealed the oxidation level. The relations between gel fraction of LDPE/EVA blend, expansion ratio, apparent density, average cell diameter and tensile properties of the foam are discussed. 8 refs. 

Figure 5.133 Comparison of tensile properties of fiber-reinforced bone cement (PMMA) and human compact bone. Reprinted, by permission, from Concise Encyclopedia of Composite Materials, A. Kelly, ed., p. 270, revised edition. Copyright 1994 by Elsevier Science Publishers, Ltd.

Various mechanical testing methods have been used to assess the bioadhesive properties of materials and formulations. Review of the literature reveals that the technique most commonly used is the tensile test [82,85]. This test provides the measure of the force needed to detach a layer of the tested material or formulation from a mucosal substrate as a function of the displacement occurring at the bioadhesive interface. Besides maximum force of detachment, another parameter provided by tensile test is the work of adhesion calculated as the area under the force versus displacement curve. Such a parameter gives more complete... 

Initially, the tensile properties of Parylene-C coated silk cloth were higher than that of the uncoated cloth (with the exception of the initial modulus). However, after a 242 kJ exposure to the xenon-arc source, the magnitude of the tensile properties of both materials were the same. 

The individual fiber properties which contribute to the tensile properties of paper include the following (8) fiber tensile strength mean fiber length fiber cross-sectional area perimeter of the average fiber cross section density of the fibrous material fraction of the fiber area bonded in the sheet and the shear strength per unit area of fiber-to-fiber bonds. 

Plastic selection ultimately depends upon the performance criteria of the product that usually includes aesthetics and cost effectiveness. Analyzing how a material is expected to perform with respect to requirements such as mechanical space, electrical, and chemical requirements combined with time and temperature can be essential to the selection process. The design engineer translates product requirements into material properties. Characteristics and properties of materials that correlate with known performances are referred to as engineering properties. They include such properties as tensile strength and modulus of elasticity, impact, hardness, chemical resistance, flammability, stress crack resistance, and temperature tolerance. Other important considerations encompass such factors as optical clarity, gloss, UV stability, and weatherability.1 248>482... 

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