Stress vs. strain curves

Numerous methods have been used to measure elastic moduli. Probably the most common test is the tensile stress-strain test (8-10). For isotropic materials. Young s modulus is the initial slope of the true stress vs. strain curve. That is,... 

Figure 3.18. Comparative stress vs. strain curves for pure iron, steel, and hardened steel. Reproduced with permission from Practical Metallurgy and Materials of Industry, Neely, J. E. Bertone, T. J., 5th ed., Prentice-Hall New Jersey, 2000.

Figure 5.2. Stress vs. strain curves for various polymers around its glass-transition temperature. The maximum in the curve that occurs at Tg is referred to as the yield point (onset of plastic deformation).

Mechanical Tensile Studies. The stress vs. strain curves for membranes having various silicon oxide solid uptakes for the four alcohol solvents are displayed in Figures 3-6. Also shown, for reference, on each of these figures is the tensile behavior of untreated Nafion in the dry add form. 

Nondestructive tests have certain advantages Including the ability to measure the elasticity of the gel on products such as jellies containing particulates. Nondestructive tests can be used to blend raw pectins to a consistent jelly grade. Also, some reports have found nondestructive Instruments to be less expensive and more reliable (63). Mitchell (60) reported that large deformations outside the linear region of a stress vs. strain curve are more difficult to Interpret and more difficult to measure than small deformations because rupture occurs at a defect In the gel and large deformations are not as reproducible. 

A pair of stress-strain rate curves for carbon steel was investigated by Parkins [ 19]. The stress vs. strain curves are compared in an inert (hot oil) atmosphere and in boiling 4 N... 

FIGURE 15.12 Stress vs. strain curves of vulcanized blends of virgin and devulcanized sample (a) and ground and virgin sample (b). The condition of devulcanization has a flow rate of 1.26 g/s, a gap size of 3 mm, an amplitude of 7.5 xm, and a barrel temperature of 120 C using the coaxial reactor. 

Fig. 8. Stress vs strain curve for PP/l%PPy nanocomposite without dispersant.

The general behaviour is characterized by a decrease of the initial modulus as well as the yield stress with temperatiue. Yielding of the material is finished at a strain of about 600. .. 900 %, afterwards there is a strain hardening. The strain hardening modulus (slop>e of the true stress vs. strain curve in the region of strain hardening) decreases with the temperature. 

Such a comparison is shown in Figure 15.5 as stress vs. strain curves for random copolymers containing varying concentrations 6 of LC (that is rigid) segments. For a given concentration 0 one can have a large... 

In brittle plastics, with a typical stress vs. strain curve as shown in (b), stress increases linearly from the center to the ends of the joint (a). In elastic materials, with a typical stress vs. strain curve as shown in (d), the shear stress distribution is non-linear (c), and stress is distributed over a larger area near the ends of the joints. ... 

Figure 1.22 shows a picture of an Instron Universal Materials Testing Machine and a diagram of the test plaque and details of the test configuration. The instrument can provide a stress vs. strain curve such as that shown in Figure 1.23. Analysis of this curve leads to several useful mechanical measurements.

Table 1.9 shows how some of the tensile measurements are made from the stress vs. strain curve in Figure 1.23. 

Figure 1.45 Stress vs. strain curves for two plastics (A) rigid polymer, below Tg has very high tensile strength, but less area under the curve = less energy to break and (B) rigid polymer, above Tg has lower tensile strength, but more area under curve = more energy to break.

The rest of this hook consists of property data on many plastics and elastomers. Chapters 2—10 contain multipoint data in the form of plots. The plastics are grouped hy the basic chemical structures of the plastics. Each of these chapters contains a short introduction that descrihes the basic chemical structures of the plastics in that chapter. The figures that follow contain the multipoint data. They are grouped by the t5rpe of data. Generally stress vs. strain curves start the chapter, followed by various modulus measurements, strength measures, other physical properties, and electrical properties. These properties are measured by the appropriate ISO or ASTM standards. 

Figure 6.41 Stress vs. strain curve at various temperatures for Arkema Rilsan BESNO P40 TL [2].

Figure 8.56 Typical stress vs. strain curves for DSM Arnitel EM400 and Arnitel EM550 TPE thermoplastic polyester elastomer resins [8].

Figure 10.37 Stress vs. strain curves at various temperatures for Solvay Advanced Polymers AvaSpire AV-621 NT unreinforced PAEK [3].

Figure 10.54 Compressive stress vs. strain curves for Solvay Advanced Polymers AvaSpire AV-722 BG20 low melt unreinforced PAEK [4],...

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