Tensile pull test ASTM

The tensile strength test [Figure 3.1 (1)] (ASTM-638) employs samples of a specified shape, typically a dogbone, as depicted in Figure 3.2. The sample is clamped at one end and pulled at a constant rate of elongation until the center of the specimen fails. 

Tensile strength, Tensile strength is evaluated by pull testing on metal lap-shear coupons, most often aluminum. The standard test method is ASTM D1002, Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-to-Metal) Alumi-... 

Direct tensile adhesion test An aluminum stud is mounted on the surface of the coating using a cyanoacrylate adhesive and then pulled to determine debonding force. ASTM D 5179... 

Tensile strength, which is a measure of the ability of a polymer to withstand pulling stresses, is usually measured using a dumbbell-shaped specimen (ASTM D-638-72 Figures 14.11 and 14.12). These test specimens are conditioned under standard conditions of humidity and temperature before testing. 

Physical Properties. Tensile test pieces were cut with an ASTM T50 die, modified by putting a radius as specified in Bell Telephone Laboratories, Inc., drawing B604844, on the junction between the tongues and the reduced section. Dumbbells of this small size were used to facilitate simultaneous irradiation in the water-cooled cell under nitrogen. These dumbbells were pulled at 2 inches a minute for both tensile strength and elongation at rupture measurements at ambient temperature. 

The "original" method, the H-pull or "H-block" test, was first standardised by ASTM together with a variant, the "U" test. In the former, two blocks of rubber are gripped in the tensile machine and in the latter a loop of cord is hooked onto one of the grips. 

Mechanical tests were carried out with an Instron 1123 mechanical test machine operated at a crosshead speed of 2 mm/min. Moduli were determined using rectangular bar specimens that were pulled in tension using an extensometer to obtain accurate strain measurements. Initial slopes of the stress-strain curves represent the moduli. Strength measurements were made using ASTM Type V tensile bars (cut after the composites were produced) that were pulled in tension, and the maximum tensile stresses attained were taken as the strength values. 

The polymers used and some of their physical properties are listed in Table I. Polymers were mixed and blended on a two-roll mill at 450 K. Samples were compression molded at 450 K for 7 min and cooled in the press with tap water for 5 min. ASTM D412 6.35-mm (Va in.) dumbbells were cut parallel to the mill grain from sheets having 1.9-mm (75 mils) thickness. Instron tensile tests were carried out at least 48 hr after molding. Pull rate was 50.8 cm/min (20 in./min). 

According to the ASTM C-884-78, delamination of the polymer mortar layer from the concrete test block or the presence of horizontal cracks in the concrete near the interface shall constitute failure. It is obvious from these results that the RPUMRPE mortar passes the ASTM C-884-78. After thermal cycling, no delamination was found in the specimens. The failure in all specimens in the shear and pull out tests occurred within the portland cement concrete substrate. These results depended on the tensile strength of the concrete substrate. 

In a tensile test, the specimen ( dogbone ) is gripped at each end and pulled apart. The dogbone shape of a specimen is chosen to minimize the likelihood to break the sample at or near the grips (jaws). The detailed shape (curvature) of a specimen is described in ASTM D 638, Test method for tensile properties of plastics. ... 

Tack is generally determined with a tensile testing machine and test blocks. The blocks are pulled apart immediately after the adhesive is applied and the blocks are joined. The result is reported in force required per square inch of bonded area to separate the blocks. Various instruments have also been developed to measure tack for specific applications. ASTM test methods include D2979 (Probe Tack) and D3121 (Rolhng Ball Tack). 

---