Ultimate tensile strength defined

The ultimate tensile strength (UTS) of a material refers to the maximum nominal stress that can be sustained by it and corresponds to the maximum load in a tension test. It is given by the stress associated with the highest point in a nominal stress-nominal stress plot. The ultimate tensile strengths of a ductile and of a brittle material are schematically illustrated in Figure 1.11. In the case of the ductile material the nominal stress decreases after reaching its maximum value because of necking. For such materials the UTS defines the onset of plastic instability. 

Table 3.1-112 Typical recrystallization temperature and ultimate tensile strength of commercial Mo and W based rod and wire materials with a defined degree of total deformation [1.118]...

Stress-strain characteristics under elongation or tensile deformation can be used to understand the mechanical behavior of polymers. Stress is defined as the force per unit area and strain is defined as dimensionless fractional increase in length. Tensile properties of a polymer can be characterized using quantities such modulus of elasticity, stiffness, elastic elongation, ultimate tensile strength, toughness, brittleness, and creep (Tripathi, 2002 Monasse and Haudin, 1995). 

The effect of ionizing radiation on plastics is influenced by the irradiation parameters, such as irradiation dose, ambient medium, dose rate, geometry of the plastic part, and irradiation temperature as well as the specific sensitivity of the basic chemical structure. General statements regarding the damage doses for a particular plastic cannot be made however, for clearly defined irradiation conditions and for one property at a time such statements are possible [13], Figure 5.117 provides the irradiation dose at which ultimate tensile strength and/or strain at break have decreased by 25% compared to the non-irradiated material for several plastics under two different irradiation conditions [13]. 

The second digit, which is usually 2, 4, 6 or 8, indicates the final degree of strain hardening, as characterised by a minimum value for the ultimate tensile strength (UTS). This digit is defined as explained below. 

C. The first creep exposure of the SIM procedure is a conventional creep test in the sense that the creep test specimen does not have a history of creep loading. However, the second and subsequent creep exposures are complicated by having thermal histories of the previous steps this complexity defines the SIM procedure. The strain results of a conceptual SIM test performed at 40% of ultimate tensile strength are plotted as a creep diagram in Fig. 9.13(a). 

Failure in the hoop direction of the pipe is defined as the event when g(X) <0. < ULT is the ultimate tensile strength of the FRP composite in the hoop direction and represents the resistance parameter in the performance function. is the circumferential stress due to externally applied loading and represents the demand in this limit state equation and is given by Eqn (5.5). Table 5.1 summarizes the random variables used in this analysis, their distribution types, means, and COVs. The data for variables in Eqns (5.2)—(5.4) are uncertain, with the most significant being the surface wheel load, F, and the importance factor, 7. Other coefficients (C, Cd, k, and kd) in Table 5.1 are uncertain because they are chosen on the basis of limited information (Ahmmad and Melchers, 1994). The approach here is to generate random numbers for each random variable according to its respective probability density function and determine if a failure event has occurred in the performance function. 

Load Sharing of Filler Particles. Comparison of ultimate strength of a propellant and its unfilled binder matrix almost always shows that the propellant has up to several times the tensile strength of the matrix. This filler reinforcement is presently thought to stem from additional crosslinks formed between filler particles and the network chains of the binder matrix (5, 8, 9, 34). Effective network chains are defined as the chain segments between crosslinks. From the classical theory of elasticity, the strength and/or modulus of an elastomer is proportional to the number of effective network chains per unit volume, N, or... 

Considering the evaluation of the life time of elastomer, Samay et al. pointed out that tensile strength has the same importance as ultimate elongation has. They proposed Braking Energy (BE) to estimate the life time of elastomer (J). Equation 1 defined BE. 

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