Tests tensile

The tensile test is an alternative to the force ductility test for the determination of the tensile properties and cohesion of bituminous binders, particularly polymer-modified binders. 

The test is performed according to CEN EN 13587 (2010) at a temperature of 5 C using the ductilometer apparatus as in the force ductility test but at a constant traction rate of 

For the tensile test, the conventional energy (average of three specimens) corresponds to an elongation of 0.2 m (400%) for example, = Eq - 

Details for calculating the deformation energy and the conventional energy, after performing the tensile test in accordance to CEN EN 13587 (2010), are given in CEN EN 13703 (2003). 

The tensile test properties of geomembranes are tested according to DIN ISO 527-1 1996 Determination of Tensile Properties, Part 1, General Principles, and DIN ISO 527-3 2002 Plastics - Determination of Tensile Properties - Part 3 Test Conditions for Films and Sheets. ASTM D638- 

The tensile test results depend on the test atmosphere, i.e. temperature and moisture conditions, test speed, and type and conditioning of the specimen used. According to the standard, the test atmosphere can be 

In the [ 45]j tensile test (ASTM D 3518,1991) shown in Fig 3.22, a uniaxial tension is applied to a ( 45°) laminate symmetric about the mid-plane to measure the strains in the longitudinal and transverse directions, and Ey. This can be accomplished by instrumenting the specimen with longitudinal and transverse element strain gauges. Therefore, the shear stress-strain relationships can be calculated from the tabulated values of and Ey, corresponding to particular values of longitudinal load, (or stress Jx over the width, b, and thickness, t, of the specimen), based on the relations derived from laminated plate theory (Petit, 1969 Rosen, 1972)  

Therefore, the unidirectional translaminar (i.e. through-thickness) shear strength can be obtained for the maximum load and the in-plane shear modulus of elasticity, Gu, taken from the initial linear portion of the unidirectional shear stress-shear strain (ti2 - y 2) curve  

FIGURE 15.33 A schematic of a hydraulic tensile testing machine. 

FIGURE 15.34 A representative stress-strain diagram for a ductile material. 

For metals, the percent reduction in area provides additional information about the material s deformation or its ductility. It is calculated by dividing the change in the cross-sectional area by the original cross-sectional area  

Elongation the increase in length produced in the gauge length of the test specimen by a tensile load. It is expressed in units of length, usually millimeters [inches] (also known as extension). 

Elastic limit the greatest stress which a material is capable of sustaining without any permanent strain remaining upon complete release of the stress. It is expressed in force per unit area, usually megapascals. 

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The paper discusses the application of dynamic indentation method and apparatus for the evaluation of viscoelastic properties of polymeric materials. The three-element model of viscoelastic material has been used to calculate the rigidity and the viscosity. Using a measurements of the indentation as a function of a current velocity change on impact with the material under test, the contact force and the displacement diagrams as a function of time are plotted. Experimental results of the testing of polyvinyl chloride cable coating by dynamic indentation method and data of the static tensile test are presented. 

Fig. 2. Illustrations of forces to which adhesive bonds are subjected, (a) A standard lap shear specimen where the black area shows the adhesive. The adherends are usually 25 mm wide and the lap area is 312.5 mm. The arrows show the direction of the normal apphcation of load, (b) A peel test where the loading configuration, shown by the arrows, is for a 180° peel test, (c) A double cantilever beam test specimen used in the evaluation of the resistance to crack propagation of an adhesive. The normal application of load is shown by the arrows. This load is appHed by a tensile testing machine or other...

The principal type of shear test specimen used in the industry, the lap shear specimen, is 2.54 cm wide and has a 3.23-cm overlap bonded by the adhesive. Adherends are chosen according to the industry aluminum for aerospace, steel for automotive, and wood for constmction appHcations. Adhesive joints made in this fashion are tested to failure in a tensile testing machine. The temperature of test, as weU as the rate of extension, are specified. Results are presented in units of pressure, where the area of the adhesive bond is considered to be the area over which the force is appHed. Although the 3.23-cm ... 

Peel tests are accompHshed using many different geometries. In the simplest peel test, the T-peel test, the adherends are identical in size, shape, and thickness. Adherends are attached at thek ends to a tensile testing machine and then separated in a "T" fashion. The temperature of the test, as well as the rate of adherend separation, is specified. The force requked to open the adhesive bond is measured and the results are reported in terms of newtons per meter (pounds per inch, ppi). There are many other peel test configurations, each dependent upon the adhesive appHcation. Such tests are well described in the ASTM hterature. 

Normalised fiber mechanical properties are expressed in terms of unit linear density. For example, in describing the action of a load on a fiber in a tensile test, units of N/tex or gram force per denier (gpd) are generally used. If this is done, the term tenacity should be used in place of stress. The tme units of stress are force per unit cross-sectional area, and the term stress should be reserved for those instances where the proper units are used. 

Ra.m Tensile. A ram tensile test has been developed to evaluate the bond-2one tensile strength of explosion-bonded composites. The specimen is designed to subject the bonded interface to a pure tensile load. The cross-section area of the specimen is the area of the aimulus between the outer and inner diameters of the specimen. The specimen typically has a very short tensile gauge length and is constmcted so as to cause failure at the bonded interface. The ultimate tensile strength and relative ductihty of the explosion-bonded interface can be obtained by this technique. 

Fig. 5. Hot workabihty of cast Nknonic 115 as determined by tensile testing using a Gleeble machine (O), heating (D), cooling 1135°C (A), cooling...

Tensile Testing. The most widely used instmment for measuring the viscoelastic properties of soHds is the tensile tester or stress—strain instmment, which extends a sample at constant rate and records the stress. Creep and stress—relaxation can also be measured. Numerous commercial instmments of various sizes and capacities are available. They vary greatiy in terms of automation, from manually operated to completely computer controlled. Some have temperature chambers, which allow measurements over a range of temperatures. Manufacturers include Instron, MTS, Tinius Olsen, Apphed Test Systems, Thwing-Albert, Shimadzu, GRC Instmments, SATEC Systems, Inc., and Monsanto. 

In addition to the above techniques, inverse gas chromatography, swelling experiments, tensile tests, mechanical analyses, and small-angle neutron scattering have been used to determine the cross-link density of cured networks (240—245). Si soHd-state nmr and chemical degradation methods have been used to characterize cured networks stmcturaHy (246). H- and H-nmr and spin echo experiments have been used to study the dynamics of cured sihcone networks (247—250). 

Methods used for the tensile testing of single fibers and fibers taken from yams and tows are discussed in ASTM D3822 and D2101. Measurement equipment used in fiber tensile testing is described in ASTM D76. An overview of test procedures and their significance is also available (3,10). 

ROR = ring-on-ring bending FP = four-point bending TT = tensile test and TP = three-point bending. 

The term P is leplaced kVfoi any test othei than a tensile test. 

Elements that can dissolve in copper, such as zinc, tin, and nickel for example, increase annealed strength by varying amounts depending on the element and the quantity in solution. The effect of selected solution hardening elements on tensile properties of annealed copper aUoys is iUustrated by the data in Table 4, where the yield strength is the stress at 0.2% offset strain in a tensile test. 

Plastic Stra.ln Ra.tlo. The plastic strain ratio is the ratio of strains measured in the width over the thickness directions in tensile tests. This ratio characterizes the abhity of materials to resist thinning during forming operations (13). In particular, it is a measure of the abhity of a sheet material to resist the thinning and failure at the base of a deep drawn cup. The plastic strain ratio is measured at 0°, 45°, and 90° relative to the rolling direction. These three plastic strain ratios Rq, R, and R q, are combined to obtain the average strain ratio, cahed the R or the R value, and its variation in strain ratio, cahed... 

Forming Limit Analysis. The ductihty of sheet and strip can be predicted from an analysis that produces a forming limit diagram (ELD), which defines critical plastic strains at fracture over a range of forming conditions. The ELD encompasses the simpler, but limited measures of ductihty represented by the percentage elongation from tensile tests and the minimum bend radius from bend tests. 

For use in code piping at the stated allowable stresses, the tensile and yield strengths listed in these tables must be verified by tensile tests at the mill such tests shall be specified in the purchase order. 

For all design temperatures, the maximum hardness shall be Rockwell C35 immediately under the thread roots. The hardness shall be taken on a flat area at least 3 mm ( A in) across, prepared by removing threads. No more material than necessary shall be removed to prepare the area. Hardness determination shall be made at the same frequency as tensile tests. 

The plastic behaviour of a material is usually measured by conducting a tensile test. Tensile testing equipment is standard in all engineering laboratories. Such equipment produces a load/displacement (F/u) curve for the material, which is then converted to a nominal stress/nominal strain, or cT l , curve (Fig. 8.10), where... 

Now, let us define the quantities usually listed as the results of a tensile test. The easiest way to do this is to show them on the (r /e curve itself (Fig. 8.1f). They are ... 

Most ceramics have enormous yield stresses. In a tensile test, at room temperature, ceramics almost all fracture long before they yield this is because their fracture toughness, which we will discuss later, is very low. Because of this, you cannot measure the yield strength of a ceramic by using a tensile test. Instead, you have to use a test which somehow suppresses fracture a compression test, for instance. The best and easiest is the hardness test the data shown here are obtained from hardness tests, which we shall discuss in a moment. 

In a tensile test, as the load increases, the specimen at first is strained elastically, that is reversibly. Above a limiting stress - the elastic limit - some of the strain is permanent this is plastic deformation. 

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