Impact testing falling weight

Rapid deformations are produced in impact tests (falling weight tests). A metal sheet coated on one side is deformed by a falling weight that has a hemispherical indentor. Deformation occurs directly or indirectly, i.e., the coated or the uncoated side of the sample is struck by the falling body and deformed (ISO6272). 

Gardner Impact Test (falling-weight test) A test for the impact resistance of rigid plastic sheets or parts. ASTM... 

Mechanical Properties. The mechanical properties of the selected blends studied, including the results of tensile, Izod impact, and falling-weight impact tests, are summarized in Table I. Generally, lower-than-expected toughening efficiency (especially for Izod impact) and data scattering were obtained because it is hard to maintain consistent moisture content of the specimens (especially for blends in which PA is the major component). The presence of the compatibilizer in all the blends resulted in consistent and substantial improvement in properties (Nos. 2, 3, and 4 vs No. 1, and No. 20 vs... 

Driers drop-weight test (falling-weight test) n. Any test of impact resistance in which known weights are dropped once or repeatedly on the test specimen. Examples are ASTM D 4272 (plastic films), D 3029, D 4226, and D 4495 (rigid PVC sheet and parts), and F 736, Section 15 (polycarbonate sheet). 

The impact sensitivity of energetic compounds is tested with a so-called fall hammer equipment. Samples are exposed to the impact of falling weights from variable heights... 

ASTM D3029, Test Methodfor Impact Resistance of Rigid Plastic S heeting orParts by Means of a Tup (Falling Weight), Vol. 8.02, ASTM, Philadelphia, Pa., 1993. 

Impact Resistance. Tests for impact resistance of porcelain enamels include falling weight tests such as a free-falling ball or a pendulum... 

Impact tests are, however, used to try to compare the impact strength of different materials. Of these tests four require specific mention. These are the Izod test, the Charpy test, the falling weight tests and the tensile impact test. 

Other impact tests widely used are the falling weight tests where a weight is allowed to fall onto a supported flat or domed surface and tensile impact tests in which a sample is subjected to a sudden shock in tension. Whilst the... 

Although the Izod and Charpy tests are widely used for plastics, other types of test are also popular. These include tensile impact tests and flexural plate (falling weight) tests. The latter is particularly useful in situations where the effects of flow anisotropy are being assessed. In addition, arbitrary end-product tests are widely used to provide reassurance that unforseen factors have not emerged to reduce the impact performance of the product. 

There are other types of impact tests for shock loading where energy is required to cause complete failure is reported. Each has their specific behaviors that can be related to specific product performance requirements. Tests include ball burst, ball or falling dart using different weights and heights, bag drop, bullet-type instantaneous impact, Charpy, dart drop, Mullen burst, tear resistance, and tub (2). 

We test the impact resistance of polymer plaques using the configuration shown in Fig. 8.8. We subject circular injection molded plaques to the shock of a falling weight with a hemispherical impacter. This test is also known as the Dart Drop Test . Samples can fail in a brittle or a ductile manner. Brittle samples often shatter. Ductile samples can split or a small disk may be punched out of their center. This test provides results that are analogous to those obtained from un-notched impact beam testing. 

Describe how we perform toughness testing on polymers with both the impact beam and the falling weight methods. Explain the different manners by which an amorphous polymer will fail above and below its glass transition temperature. 

Fall hammer test. A test of the sensitiveness of explosives to impact using a weight which falls vertically (see p. 69). 

IMPACT SENSITIVITY OR SHOCK SENSITIVITY TESTS (Drop Weight or Falling Weight Tests). A list of various tests with refs is given in Vol 1, p XVII. Brief descriptions of US Bureau of Mines (BM) Apparatus and of Picatinny Arsenal (PA) Apparatus are also given on p XVII. British test called Figure of Insensitiveness (FI) is described on p XII (See also Refs 36, 38d, 41, 42, 53, 55b,... 

Lead Block and Copper Cylinder Compression Tests (113-15) Ballistic Pendulum Test (115-16) Fragmentation Test (Geschoss-Splitter Probe (118) Impact Test by Falling Weight (118-20) Deflagration Point (Verpuf-fungstemperatur) (120) Friction Test (120-21) Rifle Bullet Test (Beschussprobe) (121)... 

The Impact Test, also called Falling Weight Test was devised by W. Will, SS 1, 209(1906) and by H. Kast, SS 4, 263 (1909) and the history of test was reviewed by H. Koenen et al in Explosivstoffe 8, 178(1958). The test differs essentially from the gap test because its pressures (several hundred, or up to several thousand atmospheres) are much lower and its time scale (hundreds of microseconds, depending on the length of the hammer) much longer. In the test conducted at NOL, a 35-mg sample of expl or propint was placed on a... 

Falling Weight (Impact) Test. Ten tests with 0.05 to 0.1 Og samples, using an apparatus having an anvil 1.27cm(0.5") in diameter, should show that the explosive is less sensitive than Picric Acid (PA)... 

US BoM impact apparatus In this test, a sample of 0.020 g of solid explosive is tested using a fixed falling weight , usually 2 kg. The explosive sample is held between two flat, parallel hardened steel cylinders as illustrated in Figure... 

Among the important tests which are made on explosives are the determinations of their sensitivity to impact and to temperature, that is, of the distance through which a falling weight must drop upon them to cause them to explode or to inflame, and of the temperatures at which they inflame, explode, or puff spontaneously. At different places different machines and apparatus are used, and the numerical results differ in consequence from laboratory to laboratory. 

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